Include <sys/socketcall.h>.

Save %ebx in call-clobbered %edx instead of stack.
Use JUMPTARGET(syscall_error) in jump insn.

sysdeps/unix/sysv/sysv4/linux/i386/socket.S

@@ -0,0 +1,54 @@
+/* Copyright (C) 1995 Free Software Foundation, Inc.
+This file is part of the GNU C Library.
+
+The GNU C Library is free software; you can redistribute it and/or
+modify it under the terms of the GNU Library General Public License as
+published by the Free Software Foundation; either version 2 of the
+License, or (at your option) any later version.
+
+The GNU C Library is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+Library General Public License for more details.
+
+You should have received a copy of the GNU Library General Public
+License along with the GNU C Library; see the file COPYING.LIB.  If
+not, write to the Free Software Foundation, Inc., 675 Mass Ave,
+Cambridge, MA 02139, USA.  */
+
+#include <sysdep.h>
+#include <sys/socketcall.h>
+
+.globl syscall_error
+
+/* The socket-oriented system calls are handled unusally in Linux.
+   They are all gated through the single `socketcall' system call number.
+   `socketcall' takes two arguments: the first is the subcode, specifying
+   which socket function is being called; and the second is a pointer to
+   the arguments to the specific function.
+
+   The .S files for the other calls just #define socket and #include this.  */
+
+ENTRY (socket)
+
+	/* Save registers.  */
+	movl %ebx, %edx
+
+	movl $SYS_socketcall, %eax	/* System call number in %eax.  */
+
+	/* Use ## so `socket' is a separate token that might be #define'd.  */
+	movl $SYS_##socket, %ebx	/* Subcode is first arg to syscall.  */
+	lea 8(%esp), %ecx		/* Address of args is 2nd arg.  */
+
+        /* Do the system call trap.  */
+	int $0x80
+
+	/* Restore registers.  */
+	movl %edx, %ebx
+
+	/* %eax is < 0 if there was an error.  */
+	testl %eax, %eax
+	jl JUMPTARGET(syscall_error)
+
+	/* Successful; return the syscall's value.  */
+	ret