PROLOGThis 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.
NAMEsys/shm.h --- XSI shared memory facility
DESCRIPTIONThe <sys/shm.h> header shall define the following symbolic constants:
- Attach read-only (else read-write).
- Round attach address to SHMLBA.
- Segment low boundary address multiple. The <sys/shm.h> header shall define the following data types through typedef:
Unsigned integer used for the number of current attaches that must be
able to store values at least as large as a type
header shall define the
structure, which shall include the following members:
struct ipc_perm shm_perm Operation permission structure. size_t shm_segsz Size of segment in bytes. pid_t shm_lpid Process ID of last shared memory operation. pid_t shm_cpid Process ID of creator. shmatt_t shm_nattch Number of current attaches. time_t shm_atime Time of last shmat(). time_t shm_dtime Time of last shmdt(). time_t shm_ctime Time of last change by shmctl().
void *shmat(int, const void *, int); int shmctl(int, int, struct shmid_ds *); int shmdt(const void *); int shmget(key_t, size_t, int);
The following sections are informative.
SEE ALSO<sys_ipc.h>, <sys_types.h> The System Interfaces volume of POSIX.1-2008, shmat(), shmctl(), shmdt(), shmget()
COPYRIGHTPortions 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 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 www.kernel.org/doc/man-pages/reporting_bugs.html .