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diff --git a/upstream/archlinux/man3p/pthread_getspecific.3p b/upstream/archlinux/man3p/pthread_getspecific.3p new file mode 100644 index 00000000..cde2510b --- /dev/null +++ b/upstream/archlinux/man3p/pthread_getspecific.3p @@ -0,0 +1,153 @@ +'\" et +.TH PTHREAD_GETSPECIFIC "3P" 2017 "IEEE/The Open Group" "POSIX Programmer's Manual" +.\" +.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 +pthread_getspecific, +pthread_setspecific +\(em thread-specific data management +.SH SYNOPSIS +.LP +.nf +#include <pthread.h> +.P +void *pthread_getspecific(pthread_key_t \fIkey\fP); +int pthread_setspecific(pthread_key_t \fIkey\fP, const void *\fIvalue\fP); +.fi +.SH DESCRIPTION +The +\fIpthread_getspecific\fR() +function shall return the value currently bound to the specified +.IR key +on behalf of the calling thread. +.P +The +\fIpthread_setspecific\fR() +function shall associate a thread-specific +.IR value +with a +.IR key +obtained via a previous call to +\fIpthread_key_create\fR(). +Different threads may bind different values to the same key. These +values are typically pointers to blocks of dynamically allocated memory +that have been reserved for use by the calling thread. +.P +The effect of calling +\fIpthread_getspecific\fR() +or +\fIpthread_setspecific\fR() +with a +.IR key +value not obtained from +\fIpthread_key_create\fR() +or after +.IR key +has been deleted with +\fIpthread_key_delete\fR() +is undefined. +.P +Both +\fIpthread_getspecific\fR() +and +\fIpthread_setspecific\fR() +may be called from a thread-specific data destructor function. A call +to +\fIpthread_getspecific\fR() +for the thread-specific data key being destroyed shall return the value +NULL, unless the value is changed (after the destructor starts) by a +call to +\fIpthread_setspecific\fR(). +Calling +\fIpthread_setspecific\fR() +from a thread-specific data destructor routine may result either in lost +storage (after at least PTHREAD_DESTRUCTOR_ITERATIONS attempts at +destruction) or in an infinite loop. +.P +Both functions may be implemented as macros. +.SH "RETURN VALUE" +The +\fIpthread_getspecific\fR() +function shall return the thread-specific data value associated +with the given +.IR key . +If no thread-specific data value is associated with +.IR key , +then the value NULL shall be returned. +.P +If successful, the +\fIpthread_setspecific\fR() +function shall return zero; otherwise, an error number shall be +returned to indicate the error. +.SH ERRORS +No errors are returned from +\fIpthread_getspecific\fR(). +.P +The +\fIpthread_setspecific\fR() +function shall fail if: +.TP +.BR ENOMEM +Insufficient memory exists to associate the non-NULL value with the key. +.P +The +\fIpthread_setspecific\fR() +function shall not return an error code of +.BR [EINTR] . +.LP +.IR "The following sections are informative." +.SH EXAMPLES +None. +.SH "APPLICATION USAGE" +None. +.SH RATIONALE +Performance and ease-of-use of +\fIpthread_getspecific\fR() +are critical for functions that rely on maintaining state in +thread-specific data. Since no errors are required to be detected by +it, and since the only error that could be detected is the use of an +invalid key, the function to +\fIpthread_getspecific\fR() +has been designed to favor speed and simplicity over error reporting. +.P +If an implementation detects that the value specified by the +.IR key +argument to +\fIpthread_setspecific\fR() +does not refer to a a key value obtained from +\fIpthread_key_create\fR() +or refers to a key that has been deleted with +\fIpthread_key_delete\fR(), +it is recommended that the function should fail and report an +.BR [EINVAL] +error. +.SH "FUTURE DIRECTIONS" +None. +.SH "SEE ALSO" +.IR "\fIpthread_key_create\fR\^(\|)" +.P +The Base Definitions volume of POSIX.1\(hy2017, +.IR "\fB<pthread.h>\fP" +.\" +.SH COPYRIGHT +Portions of this text are reprinted and reproduced in electronic form +from IEEE Std 1003.1-2017, Standard for Information Technology +-- Portable Operating System Interface (POSIX), The Open Group Base +Specifications Issue 7, 2018 Edition, +Copyright (C) 2018 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 . +.PP +Any typographical or formatting errors that appear +in this page are most likely +to have been introduced during the conversion of the source files to +man page format. To report such errors, see +https://www.kernel.org/doc/man-pages/reporting_bugs.html . |