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35 lines
912 B
Groff
35 lines
912 B
Groff
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.TH PTHREAD_ONCE 3 LinuxThreads
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.SH NAME
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pthread_once \- once-only initialization
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.SH SYNOPSIS
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#include <pthread.h>
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pthread_once_t once_control = PTHREAD_ONCE_INIT;
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int pthread_once(pthread_once_t *once_control, void (*init_routine) (void));
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.SH DESCRIPTION
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The purpose of !pthread_once! is to ensure that a piece of
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initialization code is executed at most once. The |once_control|
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argument points to a static or extern variable statically initialized
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to !PTHREAD_ONCE_INIT!.
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The first time !pthread_once! is called with a given |once_control|
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argument, it calls |init_routine| with no argument and changes the
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value of the |once_control| variable to record that initialization has
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been performed. Subsequent calls to !pthread_once! with the same
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!once_control! argument do nothing.
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.SH "RETURN VALUE"
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!pthread_once! always returns 0.
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.SH ERRORS
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None.
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.SH AUTHOR
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Xavier Leroy <Xavier.Leroy@inria.fr>
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