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diff --git a/man-pages-posix-2013/man3p/shm_unlink.3p b/man-pages-posix-2013/man3p/shm_unlink.3p new file mode 100644 index 0000000..6d19b3b --- /dev/null +++ b/man-pages-posix-2013/man3p/shm_unlink.3p @@ -0,0 +1,139 @@ +'\" et +.TH SHM_UNLINK "3P" 2013 "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 +shm_unlink +\(em remove a shared memory object +(\fBREALTIME\fP) +.SH SYNOPSIS +.LP +.nf +#include <sys/mman.h> +.P +int shm_unlink(const char *\fIname\fP); +.fi +.SH DESCRIPTION +The +\fIshm_unlink\fR() +function shall remove the name of the shared memory object named +by the string pointed to by +.IR name . +.P +If one or more references to the shared memory object exist when the +object is unlinked, the name shall be removed before +\fIshm_unlink\fR() +returns, but the removal of the memory object contents shall be postponed +until all open and map references to the shared memory object have been +removed. +.P +Even if the object continues to exist after the last +\fIshm_unlink\fR(), +reuse of the name shall subsequently cause +\fIshm_open\fR() +to behave as if no shared memory object of this name exists (that is, +\fIshm_open\fR() +will fail if O_CREAT is not set, or will create a new shared memory +object if O_CREAT is set). +.SH "RETURN VALUE" +Upon successful completion, a value of zero shall be returned. +Otherwise, a value of \(mi1 shall be returned and +.IR errno +set to indicate the error. If \(mi1 is returned, the named shared +memory object shall not be changed by this function call. +.SH ERRORS +The +\fIshm_unlink\fR() +function shall fail if: +.TP +.BR EACCES +Permission is denied to unlink the named shared memory object. +.TP +.BR ENOENT +The named shared memory object does not exist. +.P +The +\fIshm_unlink\fR() +function may fail if: +.TP +.BR ENAMETOOLONG +.br +The length of the +.IR name +argument exceeds +{_POSIX_PATH_MAX} +on systems that do not support the XSI option +or exceeds +{_XOPEN_PATH_MAX} +on XSI systems, +or has a pathname component that is longer than +{_POSIX_NAME_MAX} +on systems that do not support the XSI option +or longer than +{_XOPEN_NAME_MAX} +on XSI systems. +A call to +\fIshm_unlink\fR() +with a +.IR name +argument that contains the same shared memory object name as was +previously used in a successful +\fIshm_open\fR() +call shall not give an +.BR [ENAMETOOLONG] +error. +.LP +.IR "The following sections are informative." +.SH EXAMPLES +None. +.SH "APPLICATION USAGE" +Names of memory objects that were allocated with +\fIopen\fR() +are deleted with +\fIunlink\fR() +in the usual fashion. Names of memory objects that were allocated with +\fIshm_open\fR() +are deleted with +\fIshm_unlink\fR(). +Note that the actual memory object is not destroyed until the +last close and unmap on it have occurred if it was already in use. +.SH RATIONALE +None. +.SH "FUTURE DIRECTIONS" +A future version might require the +\fIshm_open\fR() +and +\fIshm_unlink\fR() +functions to have semantics similar to normal file system operations. +.SH "SEE ALSO" +.IR "\fIclose\fR\^(\|)", +.IR "\fImmap\fR\^(\|)", +.IR "\fImunmap\fR\^(\|)", +.IR "\fIshmat\fR\^(\|)", +.IR "\fIshmctl\fR\^(\|)", +.IR "\fIshmdt\fR\^(\|)", +.IR "\fIshm_open\fR\^(\|)" +.P +The Base Definitions volume of POSIX.1\(hy2008, +.IR "\fB<sys_mman.h>\fP" +.SH COPYRIGHT +Portions of this text are reprinted and reproduced in electronic form +from IEEE Std 1003.1, 2013 Edition, Standard for Information Technology +-- Portable Operating System Interface (POSIX), The Open Group Base +Specifications Issue 7, Copyright (C) 2013 by the Institute of +Electrical and Electronics Engineers, Inc and The Open Group. +(This is POSIX.1-2008 with the 2013 Technical Corrigendum 1 applied.) 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.unix.org/online.html . + +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 . |