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1997-10-12 05:09 Ulrich Drepper <drepper@cygnus.com> * libio/Makefile (routines): Remove iofprintf. * stdio-common/fprintf.c [USE_IN_LIBIO]: Define _IO_fprintf. * libio/filedoalloc.c: Use _G_stat64 instead of stat. * libio/fileops.c (_IO_file_open): Change to take extra argument indicating whether 32 or 64 bit mode is wanted. * libio/iofopen.c: Call _IO_file_open with extra argument set to 0. * libio/iofopen64.c: Call _IO_file_open with extra argument set to 0. * libio/iolibio.h (_IO_freopen, _IO_freopen64): Likewise. * libio/iofgetpos.c: Pretty print. * libio/iofgetpos64.c: Use _IO_fpos64_t for local variable `pos'. * manual/conf.texi: Document all the _SC_ and _CS_ constants. * manual/creature.texi: Document _LARGEFILE_SOURCE, _LARGEFILE64_SOURCE and _FILE_OFFSET_BITS. * manual/llio.texi: Document truncate and ftruncate. * manual/stdio.texi: Document positional parameters for printf. * math/Makefile (headers): Add tgmath.h. (libm-support): Remove s_lrint, s_llrint, s_lround, and s_llround and move to ... (libm-calls): ... here. Add scalbln, s_nextafterx and s_fma. * math/libm-test.c (lround_test, llround_test): Test for all FP formats by using FUNC(). * math/libm.map: Add fma, fmaf, fmal, nextafterx, nextafterxf, nextafterxl, scalbln, scalblnf, scalblnl, lrintf, lrintl, llrintf, llrintl, lroundf, lroundl, llroundf, and llroundl. * math/math.h: Document new platform specific macros from mathdef.h. Remove declaration of lrint, llrint, lround, and llround. * math/test-double.c: Define TEST_DOUBLE. * math/test-idouble.c: Likewise. * math/test-float.c: Define TEST_FLOAT. * math/test-ifloat.c: Likewise. * math/tgmath.h: New file. * math/bits/mathcalls.h: Add nextafterx, scalbln, fma, lrint, llrint, lround, and llround. Change second argument of scalbn to `int'. * sysdeps/libm-ieee754/s_fma.S: New file. * sysdeps/libm-ieee754/s_fmaf.S: New file. * sysdeps/libm-ieee754/s_fmal.S: New file. * sysdeps/libm-i387/s_fma.S: New file. * sysdeps/libm-i387/s_fmaf.S: New file. * sysdeps/libm-i387/s_fmal.S: New file. * sysdeps/libm-i387/s_llrint.S: Change to take double argument. * sysdeps/libm-i387/s_lrint.S: Likewise. * sysdeps/libm-i387/s_llrintf.S: New file. * sysdeps/libm-i387/s_llrintl.S: New file. * sysdeps/libm-i387/s_lrintf.S: New file. * sysdeps/libm-i387/s_lrintl.S: New file. * sysdeps/libm-ieee754/s_llrint.c: Remove version which works on 80bit double. * sysdeps/libm-ieee754/s_lrint.c: Likewise. * sysdeps/libm-ieee754/s_llrintf.S: New file. * sysdeps/libm-ieee754/s_llrintl.S: New file. * sysdeps/libm-ieee754/s_lrintf.S: New file. * sysdeps/libm-ieee754/s_lrintl.S: New file. * sysdeps/libm-i387/s_scalbln.c: New file. Empty file. * sysdeps/libm-i387/s_scalblnf.c: New file. Empty file. * sysdeps/libm-i387/s_scalblnl.c: New file. Empty file. * sysdeps/libm-i387/s_scalbn.c: Add scalbln as alias. * sysdeps/libm-i387/s_scalbnf.c: Add scalblnf as alias. * sysdeps/libm-i387/s_scalbnl.c: Add scalblnl as alias. * sysdeps/libm-ieee754/s_llround.c: Remove version which works on 80bit double. * sysdeps/libm-ieee754/s_lround.c: Likewise. * sysdeps/libm-ieee754/s_llroundf.c: Likewise. * sysdeps/libm-ieee754/s_llroundl.c: Likewise. * sysdeps/libm-ieee754/s_lroundf.c: Likewise. * sysdeps/libm-ieee754/s_lroundl.c: Likewise. * sysdeps/libm-ieee754/s_nextafterl.c: Add alias fo nextafterxl. * sysdeps/libm-ieee754/s_nextafterx.c: New file. * sysdeps/libm-ieee754/s_nextafterxf.c: New file. * sysdeps/libm-ieee754/s_nextafterxl.c: New file. * sysdeps/libm-ieee754/s_scalbln.c: New file. * sysdeps/libm-ieee754/s_scalblnf.c: New file. * sysdeps/libm-ieee754/s_scalblnl.c: New file. * sysdeps/libm-ieee754/s_scalbn.c: Change to take `int' as second arg. * sysdeps/libm-ieee754/s_scalbnf.c: Likewise. * sysdeps/libm-ieee754/s_scalbnl.c: Likewise. * stdlib/stdlib.h: Protect declarations of __strto*l_internal functions by #ifdefs since they are duplicated in inttypes.h. * sysdeps/wordsize-32/inttypes.h: Add definition of strtoimax and strtoumax plus needed declarations. * sysdeps/generic/confname.h (_SC_AIO_LISTIO_MAX): Fix typo. 1997-10-09 Andreas Jaeger <aj@arthur.rhein-neckar.de> * locale/programs/locfile.c (locfile_read): Correct while loop. * db2/makedb.c (main): Add missing parameter for error output. (process_input): Likewise. * resolv/gethnamaddr.c (getanswer): Rewrite a bit to avoid warning. 1997-10-12 05:05 Ulrich Drepper <drepper@cygnus.com> * libc-map: Add __bzero, __mempcpy. 1997-10-10 18:51 David S. Miller <davem@tanya.rutgers.edu> * sysdeps/unix/sysv/linux/sparc/bits/ioctls.h: Remove dependencies on kernel_termios.h 1997-10-09 10:24 Thorsten Kukuk <kukuk@vt.uni-paderborn.de> Add the changes from the Solaris 2.6 header files, use the new public defines/functions. * nis/nis_addmember.c: Updated. * nis/nis_checkpoint.c: Updated. * nis/nis_creategroup.c: updated. * nis/nis_destroygroup.c: Updated. * nis/nis_getservlist.c: Updated. * nis/nis_ismember.c: Updated. * nis/nis_lookup.c: Updated. * nis/nis_modify.c: Updated. * nis/nis_ping.c: Updated. * nis/nis_print.c: Updated. * nis/nis_print_group_entry.c: Updated. * nis/nis_remove.c: Updated. * nis/nis_removemember.c: Updated. * nis/nis_xdr.c: Updated. * nis/nss_nisplus/nisplus-alias.c: Updated. * nis/nss_nisplus/nisplus-ethers.c: Updated. * nis/nss_nisplus/nisplus-hosts.c: Updated. * nis/nss_nisplus/nisplus-network.c: Updated. * nis/nss_nisplus/nisplus-parser.c: Updated. * nis/nss_nisplus/nisplus-proto.c: Updated. * nis/nss_nisplus/nisplus-rpc.c: Updated. * nis/nss_nisplus/nisplus-service.c: Updated. * nis/rpcsvc/nis.h: Updated. * nis/rpcsvc/nis.x: Updated. * nis/rpcsvc/nis_object.x: Updated. * nis/rpcsvc/nis_tags.h: Updated. * nis/rpcsvc/nislib.h: Updated. * nis/lckcache.c: Removed, since Sun has dropped the directory signatures. The old cache version is now a security risk and not longer supported by Sun. * nis/nis_cache.c: Likewise. * nis/rpcsvc/nis_cache.h: Likewise. * nis/rpcsvc/nis_cache.x: Likewise. * nis/nis_call.c: Remove calls to the cache functions. * nis/libnsl.map: Remove cache and depending functions. * nis/nis_intern.h: Likewise. * nis/nis_add.c: Remove #include <rpcsvc/nislib.h>. * nis/nis_domain_of.c: Likewise. * nis/nis_domain_of_r.c: Likewise. * nis/nis_error.c: Likewise. * nis/nis_file.c: Likewise. * nis/nis_local_names.c: Likewise. * nis/nis_mkdir.c: Likewise. * nis/nis_rmdir.c: Likewise. * nis/nis_subr.c: Likewise. * nis/nis_verifygroup.c: Likewise. * nis/nis_clone.c: Removed, replaced by ... * nis/nis_clone_dir.c: New. * nis/nis_clone_obj.c: New. * nis/nis_clone_res.c: New. * nis/nis_table.c: Fixed bugs shown through the new clone functions. * nis/nis_defaults.c: Fixed a lot of race conditions. * nis/nis_free.c: Rewritten. * sunrpc/auth_des.c: Fix use of free'ed pointer. * nis/Makefile (libnsl-routines): Remove nis_clone, nis_cache and lckcache. Add nis_clone_dir, nis_clone_obj, and nis_clone_res. 1997-10-09 Andreas Jaeger <aj@arthur.rhein-neckar.de> * wctype/test_wctype.c (TEST): Add parens to avoid ambiguity. 1997-10-08 Andreas Schwab <schwab@issan.informatik.uni-dortmund.de> * include/features.h: Don't crash if _XOPEN_SOURCE is defined to be empty. 1997-10-09 05:54 Ulrich Drepper <drepper@cygnus.com> * nss/digits_dots.c: Place `result' in resbuf and not in `buffer'. * nss/getXXbyYY_r.c: Make sure digits_dots.c sees `resbuf' as struct and not a pointer. Little optimizations. 1997-10-09 05:00 Ulrich Drepper <drepper@cygnus.com> * sysdeps/stub/getenv.c: Remove unused file. * sysdeps/stub/lxstat.c: Likewise. * sysdeps/stub/morecore.c: Likewise. * sysdeps/stub/putenv.c: Likewise. * sysdeps/stub/sbrk.c: Likewise. * sysdeps/stub/setenv.c: Likewise. * sysdeps/stub/sysd-stdio.c: Likewise. * sysdeps/stub/sysdep.h: Likewise. Reported by Zack Weinberg <zack@rabi.phys.columbia.edu>. 1997-10-09 04:58 Ulrich Drepper <drepper@cygnus.com> * configure.in: Add __bzero definition to DWARF2 unwind test. Reported by David S. Miller <davem@caip.rutgers.edu>. 1997-10-07 Paul Eggert <eggert@twinsun.com> * intl/loadmsgcat.c (_nl_load_domain): Fix &&/|| typo when checking file size. Check for overflow when stuffing off_t into size_t. 1997-10-07 18:11 Ulrich Drepper <drepper@cygnus.com> * time/africa: Update from tzdata1997i. 1997-10-07 Andreas Jaeger <aj@arthur.rhein-neckar.de> * posix/globtest.sh: Add arguments for name of dynamic linker and call dynamic linker to execute globtest. * posix/Makefile (tests): Supply arguments to globtest.sh. 1997-10-07 Andreas Jaeger <aj@arthur.rhein-neckar.de> * nis/rpcsvc/ypupd.h: Add missing __END_DECLS. 1997-10-03 Andreas Schwab <schwab@issan.informatik.uni-dortmund.de> * libc.map: Add mempcpy, prctl. 1997-09-30 Andreas Schwab <schwab@issan.informatik.uni-dortmund.de> * sysdeps/generic/memcmp.c: Avoid warnings. * sysdeps/generic/memset.c: Likewise. * sysdeps/generic/strchr.c: Likewise. * sysdeps/generic/strlen.c: Likewise. 1997-09-29 Andreas Schwab <schwab@issan.informatik.uni-dortmund.de> * malloc/Makefile ($(objpfx)mtrace): Fix typo. 1997-09-29 Andreas Schwab <schwab@issan.informatik.uni-dortmund.de> * sysdeps/m68k/dl-machine.h (elf_machine_rela): Fix last change. The R_68K_GLOB_DAT and R_68K_JMP_SLOT relocations really ignore the addend, Richard. (elf_machine_fixup_plt): Don't add the addend. (elf_machine_plt_value): New function. * sysdeps/alpha/dl-machine.h (elf_machine_plt_value): New function. * sysdeps/sparc/sparc32/dl-machine.h (elf_machine_plt_value): New function. * sysdeps/sparc/sparc64/dl-machine.h (elf_machine_plt_value): New function. * sysdeps/powerpc/dl-machine.h (elf_machine_plt_value): New function. * sysdeps/i386/dl-machine.h (elf_machine_plt_value): New function. * elf/dl-runtime.c (fixup, profile_fixup): Don't add in the addend, instead let the machine dependent setup decide. 1997-09-20 Andreas Schwab <schwab@issan.informatik.uni-dortmund.de> * sysdeps/m68k/m68020/bits/string.h: New file. 1997-10-07 04:27 Richard Henderson <rth@cygnus.com> * Makeconfig (+includes): Add -I$(objpfx). * stdlib/longlong.h [__sparc__]: Prototype __udiv_qrnnd. * sysdeps/alpha/setjmp.S: __setjmp is the same as _setjmp. Make the former a strong symbol and the later a weak alias. * sysdeps/sparc/sparc32/setjmp.S: Likewise. * sysdeps/unix/sysv/linux/sparc/sparc64/setjmp.S: Likewise. 1997-10-06 21:01 David S. Miller <davem@tanya.rutgers.edu> * sysdeps/unix/sysv/linux/sparc/sparc64/bits/types.h: Make ino_t 64-bits. * sysdeps/unix/sysv/linux/sparc/sparc64/kernel_stat.h: Make st_ino member 64-bits as well, to match the kernel. 1997-10-06 19:35 Ulrich Drepper <drepper@cygnus.com> * sysdeps/sparc/sparc64/sub_n.S: Fix typo. Patch by Jakub Jelinek <jj@sunsite.ms.mff.cuni.cz>. 1997-10-06 01:09 Zack Weinberg <zack@rabi.phys.columbia.edu> * time/README: Correct list of files from tzcode package. Add contact information for tzcode/tzdata maintainers. Correct spelling of author's name. Compact lists. 1997-10-06 01:48 Ulrich Drepper <drepper@cygnus.com> * malloc/malloc.h: Remove hook definition without caller argument. * malloc/malloc.c: Likewise. * string/tester.c: Correct strsep test. * string/bits/string2.h: Define __string2_1bptr_p and use it. Patch by David S. Miller <davem@tanya.rutgers.edu>. * math/Makefile (routines): Add s_clog10. * math/libm-test.c: Add test for clog10. * math/libm.map: Add clog10{,f,l}. * math/bits/cmathcalls.h [__USE_GNU]: Add clog10. * sysdeps/libm-ieee754/s_clog10.c: New file. * sysdeps/libm-ieee754/s_clog10f.c: New file. * sysdeps/libm-ieee754/s_clog10l.c: New file. * manual/math.texi: Describe clog10. * config.h.in: Add USE_REGPARMS and define internal_function based on this. * configure.in: Define USE_REGPARMS for ix86 machines. * gmon/gmon.c: Mark write_hist, write_call_graph and write_bb_counts as internal functions. * inet/getnameinfo.c: Likewise for nrl_domainname. * inet/getnetgrent_r.c: Likewise for __internal_setnetgrent_reuse. * inet/rcmd.c: Likewise for __icheckhost. * intl/dcgettext.c: Likewise for category_to_name and guess_category_value. * intl/localealias.c: Likewise for read_alias_file. * io/fts.c: Likewise for fts_alloc, fts_build, fts_lfree, fts_maxarglen, fts_padjust, fts_palloc, fts_sort, and fts_stat. * libio/genops.c: Likewise for save_for_backup. * malloc/malloc.c (chunk_free, chunk_alloc, chunk_realloc, chunk_align, main_trim, heap_trim): Likewise. * malloc/mtrace.c (tr_where): Likewise. * misc/fstab.c (mnt2fs): Likewise. * misc/getttyent.c (skip, value): Likewise. * misc/syslog.c (openlog_internal): Likewise. * misc/tsearch.c (trecurse, tdestroy_internal): Likewise. * nss/nsswitch.c (nss_lookup_function, nss_parse_file, nss_getline, nss_parse_service_list, nss_new_service): Likewise. * posix/wordexp.c (parse_dollars, parse_backtick, eval_expr): Likewise. * resolv/inet_ntop.c (inet_ntop4, inet_ntop6): Likewise. * resolv/inet_pton.c (inet_pton4, inet_pton6): Likewise. * resolv/res_init.c (res_setoptions): Likewise. * stdio-common/printf_fp.c (group_number): Likewise. * stdio-common/vfprintf.c (buffered_vfprintf, group_number): Likewise. * stdlib/fmtmsg.c (internal_addseverity): Likewise. * sunrpc/auth_des.c (synchronize): Likewise. * sunrpc/auth_unix.c (marshal_new_auth): Likewise. * sunrpc/clnt_perr.c (auth_errmsg): Likewise. * sunrpc/key_call.c (key_call): Likewise. * sunprc/pmap_rmt.c (getbroadcastnets): Likewise. * sunrpc/svc_tcp.c (makefd_xprt): Likewise. * sunrpc/svcauth_des.c (cache_init, cache_spot, cache_ref, invalidate): Likewise. * sunrpc/xdr_rec.c (fix_buf_size, skip_input_bytes, flush_out, set_input_fragment, get_input_bytes): Likewise. * sysdeps/unix/sysv/linux/getsysstats.c (get_proc_path, phys_pages_info): Likewise. * sysdeps/unix/sysv/linux/if_index.c (opensock): Likewise. * sysdeps/unix/sysv/linux/poll.c (__emulate_poll): Likewise. * sysdeps/unix/sysv/linux/readv.c (__atomic_readv_replacement): Likewise. * sysdeps/unix/sysv/linux/readv.c (__atomic_writev_replacement): Likewise. * time/strptime.c (strptime_internal): Likewise. * time/tzfile.c (find_transition, compute_tzname_max): Likewise. * time/tzset.c (compute_change, tz_compute, tzset_internal): Likewise. * libc.map: Remove _libio_using_thunks, add _fp_hw and _dl_addr. * ctype/ctype.h: Pretty print. * grp/grp.h: Likewise. * include/libc-symbols.h: Likewise. * include/limits.h: Likewise. * include/values.h: Likewise. * io/fcntl.h: Likewise. * io/sys/stat.h: Likewise. * libio/stdio.h: Likewise. * malloc/malloc.h: Likewise. * misc/err.h: Likewise. * misc/regexp.h: Likewise. * misc/sys/cdefs.h: Likewise. * misc/sys/file.h: Likewise. * posix/sys/utsname.h: Likewise. * posix/sys/wait.h: Likewise. * pwd/pwd.h: Likewise. * resolv/netdb.h: Likewise. * signal/signal.h: Likewise. * stdlib/stdlib.h: Likewise. * string/endian.h: Likewise. * string/memory.h: Likewise. * sysdeps/mach/hurd/bits/fcntl.h: Likewise. * sysdeps/mach/hurd/sys/param.h: Likewise. * sysdeps/unix/sysv/linux/sys/param.h: Likewise. * termios/termios.h: Likewise. * wcsmbs/wchar.h: Likewise. * wctype/wctype.h: Likewise. * sysdeps/unix/bsd/bsd4.4/wait3.c: Use __WAIT_STATUS in definition. Implement Large File Support API. * include/features.h: Add suuport for _LARGEFILE_SOURCE, _LARGEFILE64_SOURCE, and _FILE_OFFSET_BITS. * libc.map: Add new functions for LFS. * dirent/Makefile (routines): Add readdir64 and readdir64_r. * dirent/dirent.h: Update readdir prototype for LFS and add new prototypes for above functions. * io/Makefile (routines): Add xstat64, fxstat64, lxstat64, statfs64, fstatfs64, lstat64, open64, lseek64, creat64, and ftw64. * io/creat64.c: New file. * io/fstat64.c: New file. * io/lstat64.c: New file. * io/stat64.c: New file. * io/ftw64.c: New file. * io/ftw.c: Rewrite to allow easy definition of ftw64. * io/ftw.h: Add LFS interface. * io/fcntl.h: Likewise. * io/sys/stat.h: Likewise. * io/sys/statfs.h: Likewise. * libio/Makefile (routines): Add iofgetpos64, iofopen64, iofsetpos64, freopen64, fseeko64, and ftello64. * libcio/fseeko64.c: New file. * libio/ftello64.c: New file. * libio/iofgetpos64.c: New file. * libio/iofopen64.c: New file. * libio/iofsetpos64.c: New file. * libio/fileops.c (_IO_file_fopen): Change to use _IO_off64_t. (_IO_file_attach): Likewise. (_IO_do_write): Likewise. (_IO_file_sync): Likewise. (_IO_file_seek): Likewise. (_IO_file_seekoff): Likewise. Use _G_stat64. (_IO_file_fopen64): New function. (_IO_file_jumps): Initialize showmanyc and imbue. * libio/genops.c (_IO_default_seekpos): Change to use _IO_fpos64_t. (_IO_default_seekoff): Likewise. (_IO_default_seek): Likewise. (_IO_default_showmanyc, _IO_default_imbue): New functions. * libio/iofopncook.c (_IO_cookie_seek): Change to use _IO_off64_t. * libio/iolibio.h: Add prototypes for LFS functions. * libio/ioseekoff.c: Change to use _IO_fpos64_t. * libio/ioseekpos.c: Likewise. * libio/libio.h: Define _IO_fpos64_t and _IO_off64_t. (_IO_FILE): Move _offset field to end and change type to _IO_off64_t. (_IO_seekoff, _IO_seekpos): Change prototype. * libio/libioP.h (_IO_seekoff_t, _IO_seekpos_t, _IO_seek_t): Change to use _IO_off64_t. Change prototypes for function from the *ops.c files. * libio/stdio.h: Add LFS interface definition. * libio/strops.c (_IO_str_seekoff): Change to use _IO_fpos64_t. * posix/Makefile (routines): Add pread64 and pwrite64. * posix/confstr.c: Handle _CS_LFS* requests. * posix/getconf.c: Handle LFS* requests. * sysdeps/generic/confname.h: Add _CS_LFS* constants. * posix/unistd.h: Document _LFS64_LARGEFILE and _LFS64_STDIO. Define off_t and off64_t appropriately. Change prototypes of LFS functions. * posix/sys/types.h: Add LFS types. * resources/Makefile (routines): Add getrlimit64 and setlimit64. * resource/sys/resource.h: Change prototypes of LFS functions. * stdio-common/Makefile (routines): Add tmpfile64. * stdio-common/tmpfile64.c: New file. * sysdeps/generic/_G_config.h: Define _G_fpos64_t and _G_off64_t. Define _G_OPEN64, _G_LSEEK64, _G_FSTAT64. * sysdeps/unix/sysv/linux/_G_config.h: Likewise. * sysdeps/generic/bits/resource.h: Add LFS definitions. * sysdeps/unix/bsd/sun/sunos4/bits/resource.h: Likewise. * sysdeps/unix/sysv/linux/bits/resource.h: Likewise. * sysdeps/generic/statfs.h: Use __fsblkcnt_t for some of the fields. * sysdeps/unix/sysv/linux/bits/statfs.h: Likewise. * sysdeps/unix/sysv/linux/mips/bits/statfs.h: Likewise. * sysdeps/generic/types.h: Define LFS types. * sysdeps/unix/sysv/linux/alpha/bits/types.h: Likewise. * sysdeps/unix/sysv/linux/bits/types.h: Likewise. * sysdeps/unix/sysv/linux/sparc/sparc64/bits/types.h: Likewise. * sysdeps/generic/sys/mman.h: Add LFS definitions. * sysdeps/unix/sysv/linux/sys/mman.h: Likewise. * sysdeps/generic/mach/hurd/bits/fcntl.h: Add flock LFS extensions. * sysdeps/unix/bsd/bits/fcntl.h: Likewise. * sysdeps/unix/sysv/linux/alpha/bits/fcntl.h: Likewise. * sysdeps/unix/sysv/linux/bits/fcntl.h: Likewise. * sysdeps/unix/sysv/linux/mips/bits/fcntl.h: Likewise. * sysdeps/generic/mach/hurd/bits/stat.h: Add stat LFS extensions. * sysdeps/unix/bsd/bits/stat.h: Likewise. * sysdeps/unix/bsd/osf/alpha/bits/stat.h: Likewise. * sysdeps/unix/sysv/linux/alpha/bits/stat.h: Likewise. * sysdeps/unix/sysv/linux/bits/stat.h: Likewise. * sysdeps/unix/sysv/linux/mips/bits/stat.h: Likewise. * sysdeps/unix/sysv/linux/sparc/bits/stat.h: Likewise. * sysdeps/unix/sysv/sysv4/i386/bits/stat.h: Likewise. * sysdeps/unix/sysv/sysv4/solaris2/bits/stat.h: Likewise. * sysdeps/posix/open64.c: New file. * sysdeps/stub/fstatfs64.c: New file. * sysdeps/stub/fxstat64.c: New file. * sysdeps/stub/getrlimit64.c: New file. * sysdeps/stub/lseek64.c: New file. * sysdeps/stub/lxstat64.c: New file. * sysdeps/stub/open64.c: New file. * sysdeps/stub/pread64.c: New file. * sysdeps/stub/pwrite64.c: New file. * sysdeps/stub/readdir64.c: New file. * sysdeps/stub/readdir64_r.c: New file. * sysdeps/stub/setrlimit64.c: New file. * sysdeps/stub/statfs64.c: New file. * sysdeps/stub/xstat64.c: New file. * sysdeps/unix/sysv/linux/llseek.c: Define as __llseek and make llseek and lseek64 weak aliases. * sysdeps/unix/sysv/linux/lseek64.c: New file. Empty. * sysdeps/unix/sysv/linux/alpha/bits/dirent.h: New file. * sysdeps/unix/sysv/linux/bits/dirent.h: Add LFS definitions. * sysdeps/posix/tempname.c: Add extra argument to trigger use of open64. * sysdeps/stub/tempname.c: Likewise. * stdio-common/tempnam.c: Call __stdio_gen_tempname with extra argument. * stdio-common/tmpfile.c: Likewise. * stdio-common/tmpnam.c: Likewise. * stdio-common/tmpnam_r.c: Likewise. * libio/libioP.h: Add definition ofr showmanyc and imbue callbacks. * libio/fileops.c (_IO_file_jumps): Initialize showmanyc and imbue. * libio/iofopncook.c (_IO_cookie_jumps): Likewise. * libio/iopopen.c (_IO_proc_jumps): Likewise. * libio/memstream.c (_IO_mem_jumps): Likewise. * libio/obprintf.c (_IO_obstack_jumps): Likewise. * libio/vsnprintf.c (_IO_strn_jumps): Likewise. * libio/strops.c (_IO_str_jumps): Likewise. * manual/arith.texi: Add a few words why cabs should be used. * manual/llio.texi: Describe sync, fsync, fdatasync. Tell about cleanup handlers & fcntl,lseek,write,read,close,open. * manual/process.texi: Tell about cleanup handlers & system,waitpid, wait. * manual/signal.texi: Likewise for pause. * manual/terminal.texi: Likewise for tcdrain. * manual/time.texi: Document nanosleep. * posix/exevp.c: Don't use nested function. * stdlib/ucontext.h: New file. * sysdeps/i386/sys/ucontext.h: New file. SysV/i386 API definitions. * sunrpc/xcrypt.c (hexval): Make a macro for efficiency. * sysdeps/i386/setjmp.h: Make `here` label local. * sysdeps/i386/elf/start.S: Define _fp_hw "variable". * sysdeps/stub/fstatfs.c: Correct warning. * sysdeps/stub/fxstat.c: Likewise. * sysdeps/stub/lxstat.c: Likewise. * sysdeps/unix/sysv/i386/i686/time.S: New file. 1997-10-03 20:56 Jason Merrill <jason@yorick.cygnus.com> * malloc/obstack.h (obstack_empty_p): New macro. 1997-10-04 17:41 Philip Blundell <Philip.Blundell@pobox.com> * inet/getnameinfo.c (getnameinfo): Remove spurious `#if INET6'. 1997-09-30 Zack Weinberg <zack@rabi.phys.columbia.edu> * maint.texi: Add copyright terms for libdb (Sleepycat, Harvard). Document new --with-binutils switch; delete reference to --with-gnu-as, --with-gnu-ld, --with-gnu-binutils. Add to description of --without-fp: a kernel FPU emulator is adequate (from FAQ) * INSTALL: Regenerated. 1997-09-30 17:29 Richard Henderson <rth@cygnus.com> * sysdeps/sparc/sparc32/dl-machine.h (elf_machine_rela): Move _dl_hwcap declaration to ... (elf_machine_fixup_plt): ... here.
800 lines
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800 lines
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Plaintext
@node Processes
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@chapter Processes
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@cindex process
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@dfn{Processes} are the primitive units for allocation of system
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resources. Each process has its own address space and (usually) one
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thread of control. A process executes a program; you can have multiple
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processes executing the same program, but each process has its own copy
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of the program within its own address space and executes it
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independently of the other copies.
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@cindex child process
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@cindex parent process
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Processes are organized hierarchically. Each process has a @dfn{parent
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process} which explicitly arranged to create it. The processes created
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by a given parent are called its @dfn{child processes}. A child
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inherits many of its attributes from the parent process.
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This chapter describes how a program can create, terminate, and control
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child processes. Actually, there are three distinct operations
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involved: creating a new child process, causing the new process to
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execute a program, and coordinating the completion of the child process
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with the original program.
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The @code{system} function provides a simple, portable mechanism for
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running another program; it does all three steps automatically. If you
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need more control over the details of how this is done, you can use the
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primitive functions to do each step individually instead.
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@menu
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* Running a Command:: The easy way to run another program.
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* Process Creation Concepts:: An overview of the hard way to do it.
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* Process Identification:: How to get the process ID of a process.
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* Creating a Process:: How to fork a child process.
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* Executing a File:: How to make a process execute another program.
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* Process Completion:: How to tell when a child process has completed.
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* Process Completion Status:: How to interpret the status value
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returned from a child process.
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* BSD Wait Functions:: More functions, for backward compatibility.
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* Process Creation Example:: A complete example program.
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@end menu
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@node Running a Command
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@section Running a Command
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@cindex running a command
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The easy way to run another program is to use the @code{system}
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function. This function does all the work of running a subprogram, but
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it doesn't give you much control over the details: you have to wait
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until the subprogram terminates before you can do anything else.
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@comment stdlib.h
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@comment ISO
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@deftypefun int system (const char *@var{command})
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@pindex sh
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This function executes @var{command} as a shell command. In the GNU C
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library, it always uses the default shell @code{sh} to run the command.
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In particular, it searches the directories in @code{PATH} to find
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programs to execute. The return value is @code{-1} if it wasn't
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possible to create the shell process, and otherwise is the status of the
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shell process. @xref{Process Completion}, for details on how this
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status code can be interpreted.
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This function is a cancelation point in multi-threaded programs. This
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is a problem if the thread allocates some resources (like memory, file
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descriptors, semaphores or whatever) at the time @code{system} is
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called. If the thread gets canceled these resources stay allocated
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until the program ends. To avoid this calls to @code{system} should be
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protected using cancelation handlers.
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@c ref pthread_cleanup_push / pthread_cleanup_pop
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@pindex stdlib.h
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The @code{system} function is declared in the header file
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@file{stdlib.h}.
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@end deftypefun
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@strong{Portability Note:} Some C implementations may not have any
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notion of a command processor that can execute other programs. You can
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determine whether a command processor exists by executing
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@w{@code{system (NULL)}}; if the return value is nonzero, a command
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processor is available.
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The @code{popen} and @code{pclose} functions (@pxref{Pipe to a
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Subprocess}) are closely related to the @code{system} function. They
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allow the parent process to communicate with the standard input and
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output channels of the command being executed.
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@node Process Creation Concepts
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@section Process Creation Concepts
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This section gives an overview of processes and of the steps involved in
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creating a process and making it run another program.
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@cindex process ID
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@cindex process lifetime
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Each process is named by a @dfn{process ID} number. A unique process ID
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is allocated to each process when it is created. The @dfn{lifetime} of
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a process ends when its termination is reported to its parent process;
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at that time, all of the process resources, including its process ID,
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are freed.
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@cindex creating a process
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@cindex forking a process
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@cindex child process
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@cindex parent process
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Processes are created with the @code{fork} system call (so the operation
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of creating a new process is sometimes called @dfn{forking} a process).
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The @dfn{child process} created by @code{fork} is a copy of the original
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@dfn{parent process}, except that it has its own process ID.
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After forking a child process, both the parent and child processes
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continue to execute normally. If you want your program to wait for a
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child process to finish executing before continuing, you must do this
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explicitly after the fork operation, by calling @code{wait} or
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@code{waitpid} (@pxref{Process Completion}). These functions give you
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limited information about why the child terminated---for example, its
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exit status code.
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A newly forked child process continues to execute the same program as
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its parent process, at the point where the @code{fork} call returns.
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You can use the return value from @code{fork} to tell whether the program
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is running in the parent process or the child.
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@cindex process image
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Having several processes run the same program is only occasionally
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useful. But the child can execute another program using one of the
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@code{exec} functions; see @ref{Executing a File}. The program that the
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process is executing is called its @dfn{process image}. Starting
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execution of a new program causes the process to forget all about its
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previous process image; when the new program exits, the process exits
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too, instead of returning to the previous process image.
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@node Process Identification
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@section Process Identification
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The @code{pid_t} data type represents process IDs. You can get the
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process ID of a process by calling @code{getpid}. The function
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@code{getppid} returns the process ID of the parent of the current
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process (this is also known as the @dfn{parent process ID}). Your
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program should include the header files @file{unistd.h} and
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@file{sys/types.h} to use these functions.
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@pindex sys/types.h
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@pindex unistd.h
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@comment sys/types.h
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@comment POSIX.1
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@deftp {Data Type} pid_t
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The @code{pid_t} data type is a signed integer type which is capable
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of representing a process ID. In the GNU library, this is an @code{int}.
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@end deftp
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@comment unistd.h
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@comment POSIX.1
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@deftypefun pid_t getpid (void)
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The @code{getpid} function returns the process ID of the current process.
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@end deftypefun
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@comment unistd.h
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@comment POSIX.1
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@deftypefun pid_t getppid (void)
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The @code{getppid} function returns the process ID of the parent of the
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current process.
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@end deftypefun
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@node Creating a Process
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@section Creating a Process
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The @code{fork} function is the primitive for creating a process.
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It is declared in the header file @file{unistd.h}.
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@pindex unistd.h
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@comment unistd.h
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@comment POSIX.1
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@deftypefun pid_t fork (void)
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The @code{fork} function creates a new process.
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If the operation is successful, there are then both parent and child
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processes and both see @code{fork} return, but with different values: it
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returns a value of @code{0} in the child process and returns the child's
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process ID in the parent process.
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If process creation failed, @code{fork} returns a value of @code{-1} in
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the parent process. The following @code{errno} error conditions are
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defined for @code{fork}:
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@table @code
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@item EAGAIN
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There aren't enough system resources to create another process, or the
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user already has too many processes running. This means exceeding the
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@code{RLIMIT_NPROC} resource limit, which can usually be increased;
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@pxref{Limits on Resources}.
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@item ENOMEM
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The process requires more space than the system can supply.
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@end table
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@end deftypefun
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The specific attributes of the child process that differ from the
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parent process are:
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@itemize @bullet
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@item
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The child process has its own unique process ID.
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@item
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The parent process ID of the child process is the process ID of its
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parent process.
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@item
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The child process gets its own copies of the parent process's open file
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descriptors. Subsequently changing attributes of the file descriptors
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in the parent process won't affect the file descriptors in the child,
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and vice versa. @xref{Control Operations}. However, the file position
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associated with each descriptor is shared by both processes;
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@pxref{File Position}.
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@item
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The elapsed processor times for the child process are set to zero;
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see @ref{Processor Time}.
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@item
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The child doesn't inherit file locks set by the parent process.
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@c !!! flock locks shared
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@xref{Control Operations}.
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@item
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The child doesn't inherit alarms set by the parent process.
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@xref{Setting an Alarm}.
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@item
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The set of pending signals (@pxref{Delivery of Signal}) for the child
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process is cleared. (The child process inherits its mask of blocked
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signals and signal actions from the parent process.)
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@end itemize
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@comment unistd.h
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@comment BSD
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@deftypefun pid_t vfork (void)
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The @code{vfork} function is similar to @code{fork} but on systems it
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is more efficient; however, there are restrictions you must follow to
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use it safely.
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While @code{fork} makes a complete copy of the calling process's
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address space and allows both the parent and child to execute
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independently, @code{vfork} does not make this copy. Instead, the
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child process created with @code{vfork} shares its parent's address
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space until it calls exits or one of the @code{exec} functions. In the
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meantime, the parent process suspends execution.
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You must be very careful not to allow the child process created with
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@code{vfork} to modify any global data or even local variables shared
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with the parent. Furthermore, the child process cannot return from (or
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do a long jump out of) the function that called @code{vfork}! This
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would leave the parent process's control information very confused. If
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in doubt, use @code{fork} instead.
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Some operating systems don't really implement @code{vfork}. The GNU C
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library permits you to use @code{vfork} on all systems, but actually
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executes @code{fork} if @code{vfork} isn't available. If you follow
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the proper precautions for using @code{vfork}, your program will still
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work even if the system uses @code{fork} instead.
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@end deftypefun
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@node Executing a File
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@section Executing a File
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@cindex executing a file
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@cindex @code{exec} functions
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This section describes the @code{exec} family of functions, for executing
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a file as a process image. You can use these functions to make a child
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process execute a new program after it has been forked.
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@pindex unistd.h
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The functions in this family differ in how you specify the arguments,
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but otherwise they all do the same thing. They are declared in the
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header file @file{unistd.h}.
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@comment unistd.h
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@comment POSIX.1
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@deftypefun int execv (const char *@var{filename}, char *const @var{argv}@t{[]})
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The @code{execv} function executes the file named by @var{filename} as a
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new process image.
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The @var{argv} argument is an array of null-terminated strings that is
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used to provide a value for the @code{argv} argument to the @code{main}
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function of the program to be executed. The last element of this array
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must be a null pointer. By convention, the first element of this array
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is the file name of the program sans directory names. @xref{Program
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Arguments}, for full details on how programs can access these arguments.
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The environment for the new process image is taken from the
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@code{environ} variable of the current process image; see
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@ref{Environment Variables}, for information about environments.
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@end deftypefun
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@comment unistd.h
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@comment POSIX.1
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@deftypefun int execl (const char *@var{filename}, const char *@var{arg0}, @dots{})
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This is similar to @code{execv}, but the @var{argv} strings are
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specified individually instead of as an array. A null pointer must be
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passed as the last such argument.
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@end deftypefun
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@comment unistd.h
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@comment POSIX.1
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@deftypefun int execve (const char *@var{filename}, char *const @var{argv}@t{[]}, char *const @var{env}@t{[]})
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This is similar to @code{execv}, but permits you to specify the environment
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for the new program explicitly as the @var{env} argument. This should
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be an array of strings in the same format as for the @code{environ}
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variable; see @ref{Environment Access}.
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@end deftypefun
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@comment unistd.h
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@comment POSIX.1
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@deftypefun int execle (const char *@var{filename}, const char *@var{arg0}, char *const @var{env}@t{[]}, @dots{})
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This is similar to @code{execl}, but permits you to specify the
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environment for the new program explicitly. The environment argument is
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passed following the null pointer that marks the last @var{argv}
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argument, and should be an array of strings in the same format as for
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the @code{environ} variable.
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@end deftypefun
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@comment unistd.h
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@comment POSIX.1
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@deftypefun int execvp (const char *@var{filename}, char *const @var{argv}@t{[]})
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The @code{execvp} function is similar to @code{execv}, except that it
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searches the directories listed in the @code{PATH} environment variable
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(@pxref{Standard Environment}) to find the full file name of a
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file from @var{filename} if @var{filename} does not contain a slash.
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This function is useful for executing system utility programs, because
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it looks for them in the places that the user has chosen. Shells use it
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to run the commands that users type.
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@end deftypefun
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@comment unistd.h
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@comment POSIX.1
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@deftypefun int execlp (const char *@var{filename}, const char *@var{arg0}, @dots{})
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This function is like @code{execl}, except that it performs the same
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file name searching as the @code{execvp} function.
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@end deftypefun
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The size of the argument list and environment list taken together must
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not be greater than @code{ARG_MAX} bytes. @xref{General Limits}. In
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the GNU system, the size (which compares against @code{ARG_MAX})
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includes, for each string, the number of characters in the string, plus
|
|
the size of a @code{char *}, plus one, rounded up to a multiple of the
|
|
size of a @code{char *}. Other systems may have somewhat different
|
|
rules for counting.
|
|
|
|
These functions normally don't return, since execution of a new program
|
|
causes the currently executing program to go away completely. A value
|
|
of @code{-1} is returned in the event of a failure. In addition to the
|
|
usual file name errors (@pxref{File Name Errors}), the following
|
|
@code{errno} error conditions are defined for these functions:
|
|
|
|
@table @code
|
|
@item E2BIG
|
|
The combined size of the new program's argument list and environment
|
|
list is larger than @code{ARG_MAX} bytes. The GNU system has no
|
|
specific limit on the argument list size, so this error code cannot
|
|
result, but you may get @code{ENOMEM} instead if the arguments are too
|
|
big for available memory.
|
|
|
|
@item ENOEXEC
|
|
The specified file can't be executed because it isn't in the right format.
|
|
|
|
@item ENOMEM
|
|
Executing the specified file requires more storage than is available.
|
|
@end table
|
|
|
|
If execution of the new file succeeds, it updates the access time field
|
|
of the file as if the file had been read. @xref{File Times}, for more
|
|
details about access times of files.
|
|
|
|
The point at which the file is closed again is not specified, but
|
|
is at some point before the process exits or before another process
|
|
image is executed.
|
|
|
|
Executing a new process image completely changes the contents of memory,
|
|
copying only the argument and environment strings to new locations. But
|
|
many other attributes of the process are unchanged:
|
|
|
|
@itemize @bullet
|
|
@item
|
|
The process ID and the parent process ID. @xref{Process Creation Concepts}.
|
|
|
|
@item
|
|
Session and process group membership. @xref{Concepts of Job Control}.
|
|
|
|
@item
|
|
Real user ID and group ID, and supplementary group IDs. @xref{Process
|
|
Persona}.
|
|
|
|
@item
|
|
Pending alarms. @xref{Setting an Alarm}.
|
|
|
|
@item
|
|
Current working directory and root directory. @xref{Working
|
|
Directory}. In the GNU system, the root directory is not copied when
|
|
executing a setuid program; instead the system default root directory
|
|
is used for the new program.
|
|
|
|
@item
|
|
File mode creation mask. @xref{Setting Permissions}.
|
|
|
|
@item
|
|
Process signal mask; see @ref{Process Signal Mask}.
|
|
|
|
@item
|
|
Pending signals; see @ref{Blocking Signals}.
|
|
|
|
@item
|
|
Elapsed processor time associated with the process; see @ref{Processor Time}.
|
|
@end itemize
|
|
|
|
If the set-user-ID and set-group-ID mode bits of the process image file
|
|
are set, this affects the effective user ID and effective group ID
|
|
(respectively) of the process. These concepts are discussed in detail
|
|
in @ref{Process Persona}.
|
|
|
|
Signals that are set to be ignored in the existing process image are
|
|
also set to be ignored in the new process image. All other signals are
|
|
set to the default action in the new process image. For more
|
|
information about signals, see @ref{Signal Handling}.
|
|
|
|
File descriptors open in the existing process image remain open in the
|
|
new process image, unless they have the @code{FD_CLOEXEC}
|
|
(close-on-exec) flag set. The files that remain open inherit all
|
|
attributes of the open file description from the existing process image,
|
|
including file locks. File descriptors are discussed in @ref{Low-Level I/O}.
|
|
|
|
Streams, by contrast, cannot survive through @code{exec} functions,
|
|
because they are located in the memory of the process itself. The new
|
|
process image has no streams except those it creates afresh. Each of
|
|
the streams in the pre-@code{exec} process image has a descriptor inside
|
|
it, and these descriptors do survive through @code{exec} (provided that
|
|
they do not have @code{FD_CLOEXEC} set). The new process image can
|
|
reconnect these to new streams using @code{fdopen} (@pxref{Descriptors
|
|
and Streams}).
|
|
|
|
@node Process Completion
|
|
@section Process Completion
|
|
@cindex process completion
|
|
@cindex waiting for completion of child process
|
|
@cindex testing exit status of child process
|
|
|
|
The functions described in this section are used to wait for a child
|
|
process to terminate or stop, and determine its status. These functions
|
|
are declared in the header file @file{sys/wait.h}.
|
|
@pindex sys/wait.h
|
|
|
|
@comment sys/wait.h
|
|
@comment POSIX.1
|
|
@deftypefun pid_t waitpid (pid_t @var{pid}, int *@var{status-ptr}, int @var{options})
|
|
The @code{waitpid} function is used to request status information from a
|
|
child process whose process ID is @var{pid}. Normally, the calling
|
|
process is suspended until the child process makes status information
|
|
available by terminating.
|
|
|
|
Other values for the @var{pid} argument have special interpretations. A
|
|
value of @code{-1} or @code{WAIT_ANY} requests status information for
|
|
any child process; a value of @code{0} or @code{WAIT_MYPGRP} requests
|
|
information for any child process in the same process group as the
|
|
calling process; and any other negative value @minus{} @var{pgid}
|
|
requests information for any child process whose process group ID is
|
|
@var{pgid}.
|
|
|
|
If status information for a child process is available immediately, this
|
|
function returns immediately without waiting. If more than one eligible
|
|
child process has status information available, one of them is chosen
|
|
randomly, and its status is returned immediately. To get the status
|
|
from the other eligible child processes, you need to call @code{waitpid}
|
|
again.
|
|
|
|
The @var{options} argument is a bit mask. Its value should be the
|
|
bitwise OR (that is, the @samp{|} operator) of zero or more of the
|
|
@code{WNOHANG} and @code{WUNTRACED} flags. You can use the
|
|
@code{WNOHANG} flag to indicate that the parent process shouldn't wait;
|
|
and the @code{WUNTRACED} flag to request status information from stopped
|
|
processes as well as processes that have terminated.
|
|
|
|
The status information from the child process is stored in the object
|
|
that @var{status-ptr} points to, unless @var{status-ptr} is a null pointer.
|
|
|
|
This function is a cancelation point in multi-threaded programs. This
|
|
is a problem if the thread allocates some resources (like memory, file
|
|
descriptors, semaphores or whatever) at the time @code{waitpid} is
|
|
called. If the thread gets canceled these resources stay allocated
|
|
until the program ends. To avoid this calls to @code{waitpid} should be
|
|
protected using cancelation handlers.
|
|
@c ref pthread_cleanup_push / pthread_cleanup_pop
|
|
|
|
The return value is normally the process ID of the child process whose
|
|
status is reported. If the @code{WNOHANG} option was specified and no
|
|
child process is waiting to be noticed, the value is zero. A value of
|
|
@code{-1} is returned in case of error. The following @code{errno}
|
|
error conditions are defined for this function:
|
|
|
|
@table @code
|
|
@item EINTR
|
|
The function was interrupted by delivery of a signal to the calling
|
|
process. @xref{Interrupted Primitives}.
|
|
|
|
@item ECHILD
|
|
There are no child processes to wait for, or the specified @var{pid}
|
|
is not a child of the calling process.
|
|
|
|
@item EINVAL
|
|
An invalid value was provided for the @var{options} argument.
|
|
@end table
|
|
@end deftypefun
|
|
|
|
These symbolic constants are defined as values for the @var{pid} argument
|
|
to the @code{waitpid} function.
|
|
|
|
@comment Extra blank lines make it look better.
|
|
@table @code
|
|
@item WAIT_ANY
|
|
|
|
This constant macro (whose value is @code{-1}) specifies that
|
|
@code{waitpid} should return status information about any child process.
|
|
|
|
|
|
@item WAIT_MYPGRP
|
|
This constant (with value @code{0}) specifies that @code{waitpid} should
|
|
return status information about any child process in the same process
|
|
group as the calling process.
|
|
@end table
|
|
|
|
These symbolic constants are defined as flags for the @var{options}
|
|
argument to the @code{waitpid} function. You can bitwise-OR the flags
|
|
together to obtain a value to use as the argument.
|
|
|
|
@table @code
|
|
@item WNOHANG
|
|
|
|
This flag specifies that @code{waitpid} should return immediately
|
|
instead of waiting, if there is no child process ready to be noticed.
|
|
|
|
@item WUNTRACED
|
|
|
|
This flag specifies that @code{waitpid} should report the status of any
|
|
child processes that have been stopped as well as those that have
|
|
terminated.
|
|
@end table
|
|
|
|
@comment sys/wait.h
|
|
@comment POSIX.1
|
|
@deftypefun pid_t wait (int *@var{status-ptr})
|
|
This is a simplified version of @code{waitpid}, and is used to wait
|
|
until any one child process terminates. The call:
|
|
|
|
@smallexample
|
|
wait (&status)
|
|
@end smallexample
|
|
|
|
@noindent
|
|
is exactly equivalent to:
|
|
|
|
@smallexample
|
|
waitpid (-1, &status, 0)
|
|
@end smallexample
|
|
|
|
This function is a cancelation point in multi-threaded programs. This
|
|
is a problem if the thread allocates some resources (like memory, file
|
|
descriptors, semaphores or whatever) at the time @code{wait} is
|
|
called. If the thread gets canceled these resources stay allocated
|
|
until the program ends. To avoid this calls to @code{wait} should be
|
|
protected using cancelation handlers.
|
|
@c ref pthread_cleanup_push / pthread_cleanup_pop
|
|
@end deftypefun
|
|
|
|
@comment sys/wait.h
|
|
@comment BSD
|
|
@deftypefun pid_t wait4 (pid_t @var{pid}, int *@var{status-ptr}, int @var{options}, struct rusage *@var{usage})
|
|
If @var{usage} is a null pointer, @code{wait4} is equivalent to
|
|
@code{waitpid (@var{pid}, @var{status-ptr}, @var{options})}.
|
|
|
|
If @var{usage} is not null, @code{wait4} stores usage figures for the
|
|
child process in @code{*@var{rusage}} (but only if the child has
|
|
terminated, not if it has stopped). @xref{Resource Usage}.
|
|
|
|
This function is a BSD extension.
|
|
@end deftypefun
|
|
|
|
Here's an example of how to use @code{waitpid} to get the status from
|
|
all child processes that have terminated, without ever waiting. This
|
|
function is designed to be a handler for @code{SIGCHLD}, the signal that
|
|
indicates that at least one child process has terminated.
|
|
|
|
@smallexample
|
|
@group
|
|
void
|
|
sigchld_handler (int signum)
|
|
@{
|
|
int pid;
|
|
int status;
|
|
while (1)
|
|
@{
|
|
pid = waitpid (WAIT_ANY, &status, WNOHANG);
|
|
if (pid < 0)
|
|
@{
|
|
perror ("waitpid");
|
|
break;
|
|
@}
|
|
if (pid == 0)
|
|
break;
|
|
notice_termination (pid, status);
|
|
@}
|
|
@}
|
|
@end group
|
|
@end smallexample
|
|
|
|
@node Process Completion Status
|
|
@section Process Completion Status
|
|
|
|
If the exit status value (@pxref{Program Termination}) of the child
|
|
process is zero, then the status value reported by @code{waitpid} or
|
|
@code{wait} is also zero. You can test for other kinds of information
|
|
encoded in the returned status value using the following macros.
|
|
These macros are defined in the header file @file{sys/wait.h}.
|
|
@pindex sys/wait.h
|
|
|
|
@comment sys/wait.h
|
|
@comment POSIX.1
|
|
@deftypefn Macro int WIFEXITED (int @var{status})
|
|
This macro returns a nonzero value if the child process terminated
|
|
normally with @code{exit} or @code{_exit}.
|
|
@end deftypefn
|
|
|
|
@comment sys/wait.h
|
|
@comment POSIX.1
|
|
@deftypefn Macro int WEXITSTATUS (int @var{status})
|
|
If @code{WIFEXITED} is true of @var{status}, this macro returns the
|
|
low-order 8 bits of the exit status value from the child process.
|
|
@xref{Exit Status}.
|
|
@end deftypefn
|
|
|
|
@comment sys/wait.h
|
|
@comment POSIX.1
|
|
@deftypefn Macro int WIFSIGNALED (int @var{status})
|
|
This macro returns a nonzero value if the child process terminated
|
|
because it received a signal that was not handled.
|
|
@xref{Signal Handling}.
|
|
@end deftypefn
|
|
|
|
@comment sys/wait.h
|
|
@comment POSIX.1
|
|
@deftypefn Macro int WTERMSIG (int @var{status})
|
|
If @code{WIFSIGNALED} is true of @var{status}, this macro returns the
|
|
signal number of the signal that terminated the child process.
|
|
@end deftypefn
|
|
|
|
@comment sys/wait.h
|
|
@comment BSD
|
|
@deftypefn Macro int WCOREDUMP (int @var{status})
|
|
This macro returns a nonzero value if the child process terminated
|
|
and produced a core dump.
|
|
@end deftypefn
|
|
|
|
@comment sys/wait.h
|
|
@comment POSIX.1
|
|
@deftypefn Macro int WIFSTOPPED (int @var{status})
|
|
This macro returns a nonzero value if the child process is stopped.
|
|
@end deftypefn
|
|
|
|
@comment sys/wait.h
|
|
@comment POSIX.1
|
|
@deftypefn Macro int WSTOPSIG (int @var{status})
|
|
If @code{WIFSTOPPED} is true of @var{status}, this macro returns the
|
|
signal number of the signal that caused the child process to stop.
|
|
@end deftypefn
|
|
|
|
|
|
@node BSD Wait Functions
|
|
@section BSD Process Wait Functions
|
|
|
|
The GNU library also provides these related facilities for compatibility
|
|
with BSD Unix. BSD uses the @code{union wait} data type to represent
|
|
status values rather than an @code{int}. The two representations are
|
|
actually interchangeable; they describe the same bit patterns. The GNU
|
|
C Library defines macros such as @code{WEXITSTATUS} so that they will
|
|
work on either kind of object, and the @code{wait} function is defined
|
|
to accept either type of pointer as its @var{status-ptr} argument.
|
|
|
|
These functions are declared in @file{sys/wait.h}.
|
|
@pindex sys/wait.h
|
|
|
|
@comment sys/wait.h
|
|
@comment BSD
|
|
@deftp {Data Type} {union wait}
|
|
This data type represents program termination status values. It has
|
|
the following members:
|
|
|
|
@table @code
|
|
@item int w_termsig
|
|
The value of this member is the same as the result of the
|
|
@code{WTERMSIG} macro.
|
|
|
|
@item int w_coredump
|
|
The value of this member is the same as the result of the
|
|
@code{WCOREDUMP} macro.
|
|
|
|
@item int w_retcode
|
|
The value of this member is the same as the result of the
|
|
@code{WEXITSTATUS} macro.
|
|
|
|
@item int w_stopsig
|
|
The value of this member is the same as the result of the
|
|
@code{WSTOPSIG} macro.
|
|
@end table
|
|
|
|
Instead of accessing these members directly, you should use the
|
|
equivalent macros.
|
|
@end deftp
|
|
|
|
The @code{wait3} function is the predecessor to @code{wait4}, which is
|
|
more flexible. @code{wait3} is now obsolete.
|
|
|
|
@comment sys/wait.h
|
|
@comment BSD
|
|
@deftypefun pid_t wait3 (union wait *@var{status-ptr}, int @var{options}, struct rusage *@var{usage})
|
|
If @var{usage} is a null pointer, @code{wait3} is equivalent to
|
|
@code{waitpid (-1, @var{status-ptr}, @var{options})}.
|
|
|
|
If @var{usage} is not null, @code{wait3} stores usage figures for the
|
|
child process in @code{*@var{rusage}} (but only if the child has
|
|
terminated, not if it has stopped). @xref{Resource Usage}.
|
|
@end deftypefun
|
|
|
|
@node Process Creation Example
|
|
@section Process Creation Example
|
|
|
|
Here is an example program showing how you might write a function
|
|
similar to the built-in @code{system}. It executes its @var{command}
|
|
argument using the equivalent of @samp{sh -c @var{command}}.
|
|
|
|
@smallexample
|
|
#include <stddef.h>
|
|
#include <stdlib.h>
|
|
#include <unistd.h>
|
|
#include <sys/types.h>
|
|
#include <sys/wait.h>
|
|
|
|
/* @r{Execute the command using this shell program.} */
|
|
#define SHELL "/bin/sh"
|
|
|
|
@group
|
|
int
|
|
my_system (const char *command)
|
|
@{
|
|
int status;
|
|
pid_t pid;
|
|
@end group
|
|
|
|
pid = fork ();
|
|
if (pid == 0)
|
|
@{
|
|
/* @r{This is the child process. Execute the shell command.} */
|
|
execl (SHELL, SHELL, "-c", command, NULL);
|
|
_exit (EXIT_FAILURE);
|
|
@}
|
|
else if (pid < 0)
|
|
/* @r{The fork failed. Report failure.} */
|
|
status = -1;
|
|
else
|
|
/* @r{This is the parent process. Wait for the child to complete.} */
|
|
if (waitpid (pid, &status, 0) != pid)
|
|
status = -1;
|
|
return status;
|
|
@}
|
|
@end smallexample
|
|
|
|
@comment Yes, this example has been tested.
|
|
|
|
There are a couple of things you should pay attention to in this
|
|
example.
|
|
|
|
Remember that the first @code{argv} argument supplied to the program
|
|
represents the name of the program being executed. That is why, in the
|
|
call to @code{execl}, @code{SHELL} is supplied once to name the program
|
|
to execute and a second time to supply a value for @code{argv[0]}.
|
|
|
|
The @code{execl} call in the child process doesn't return if it is
|
|
successful. If it fails, you must do something to make the child
|
|
process terminate. Just returning a bad status code with @code{return}
|
|
would leave two processes running the original program. Instead, the
|
|
right behavior is for the child process to report failure to its parent
|
|
process.
|
|
|
|
Call @code{_exit} to accomplish this. The reason for using @code{_exit}
|
|
instead of @code{exit} is to avoid flushing fully buffered streams such
|
|
as @code{stdout}. The buffers of these streams probably contain data
|
|
that was copied from the parent process by the @code{fork}, data that
|
|
will be output eventually by the parent process. Calling @code{exit} in
|
|
the child would output the data twice. @xref{Termination Internals}.
|