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diff --git a/man-pages-posix-2003/man3p/sem_init.3p b/man-pages-posix-2003/man3p/sem_init.3p new file mode 100644 index 0000000..ae63e3c --- /dev/null +++ b/man-pages-posix-2003/man3p/sem_init.3p @@ -0,0 +1,104 @@ +.\" Copyright (c) 2001-2003 The Open Group, All Rights Reserved +.TH "SEM_INIT" 3P 2003 "IEEE/The Open Group" "POSIX Programmer's Manual" +.\" sem_init +.SH PROLOG +This manual page is part of the POSIX Programmer's Manual. +The Linux implementation of this interface may differ (consult +the corresponding Linux manual page for details of Linux behavior), +or the interface may not be implemented on Linux. +.SH NAME +sem_init \- initialize an unnamed semaphore (\fBREALTIME\fP) +.SH SYNOPSIS +.LP +\fB#include <semaphore.h> +.br +.sp +int sem_init(sem_t *\fP\fIsem\fP\fB, int\fP \fIpshared\fP\fB, unsigned\fP +\fIvalue\fP\fB); \fP +\fB +.br +\fP +.SH DESCRIPTION +.LP +The \fIsem_init\fP() function shall initialize the unnamed semaphore +referred to by \fIsem\fP. The value of the initialized +semaphore shall be \fIvalue\fP. Following a successful call to \fIsem_init\fP(), +the semaphore may be used in subsequent calls to +\fIsem_wait\fP(), \fIsem_trywait\fP(), \fIsem_post\fP(), and \fIsem_destroy\fP(). +This +semaphore shall remain usable until the semaphore is destroyed. +.LP +If the \fIpshared\fP argument has a non-zero value, then the semaphore +is shared between processes; in this case, any process +that can access the semaphore \fIsem\fP can use \fIsem\fP for performing +\fIsem_wait\fP(), \fIsem_trywait\fP(), \fIsem_post\fP(), and \fIsem_destroy\fP() +operations. +.LP +Only \fIsem\fP itself may be used for performing synchronization. +The result of referring to copies of \fIsem\fP in calls to +\fIsem_wait\fP(), \fIsem_trywait\fP(), \fIsem_post\fP(), and \fIsem_destroy\fP() +is +undefined. +.LP +If the \fIpshared\fP argument is zero, then the semaphore is shared +between threads of the process; any thread in this process +can use \fIsem\fP for performing \fIsem_wait\fP(), \fIsem_trywait\fP(), +\fIsem_post\fP(), and \fIsem_destroy\fP() operations. The use of the +semaphore by threads other than those created +in the same process is undefined. +.LP +Attempting to initialize an already initialized semaphore results +in undefined behavior. +.SH RETURN VALUE +.LP +Upon successful completion, the \fIsem_init\fP() function shall initialize +the semaphore in \fIsem\fP. Otherwise, it shall +return -1 and set \fIerrno\fP to indicate the error. +.SH ERRORS +.LP +The \fIsem_init\fP() function shall fail if: +.TP 7 +.B EINVAL +The \fIvalue\fP argument exceeds {SEM_VALUE_MAX}. +.TP 7 +.B ENOSPC +A resource required to initialize the semaphore has been exhausted, +or the limit on semaphores ( {SEM_NSEMS_MAX}) has been +reached. +.TP 7 +.B EPERM +The process lacks the appropriate privileges to initialize the semaphore. +.sp +.LP +\fIThe following sections are informative.\fP +.SH EXAMPLES +.LP +None. +.SH APPLICATION USAGE +.LP +The \fIsem_init\fP() function is part of the Semaphores option and +need not be available on all implementations. +.SH RATIONALE +.LP +Although this volume of IEEE\ Std\ 1003.1-2001 fails to specify a +successful return value, it is likely that a later +version may require the implementation to return a value of zero if +the call to \fIsem_init\fP() is successful. +.SH FUTURE DIRECTIONS +.LP +None. +.SH SEE ALSO +.LP +\fIsem_destroy\fP(), \fIsem_post\fP(), \fIsem_timedwait\fP(), \fIsem_trywait\fP(), +\fIsem_wait\fP(), the Base Definitions volume of IEEE\ Std\ 1003.1-2001, +\fI<semaphore.h>\fP +.SH COPYRIGHT +Portions of this text are reprinted and reproduced in electronic form +from IEEE Std 1003.1, 2003 Edition, Standard for Information Technology +-- Portable Operating System Interface (POSIX), The Open Group Base +Specifications Issue 6, Copyright (C) 2001-2003 by the Institute of +Electrical and Electronics Engineers, Inc and The Open Group. In the +event of any discrepancy between this version and the original IEEE and +The Open Group Standard, the original IEEE and The Open Group Standard +is the referee document. The original Standard can be obtained online at +http://www.opengroup.org/unix/online.html . |