.\" Copyright (c) 2001-2003 The Open Group, All Rights Reserved .TH "MLOCKALL" P 2003 "IEEE/The Open Group" "POSIX Programmer's Manual" .\" mlockall .SH NAME mlockall, munlockall \- lock/unlock the address space of a process (\fBREALTIME\fP) .SH SYNOPSIS .LP \fB#include .br .sp int mlockall(int\fP \fIflags\fP\fB); .br int munlockall(void); \fP \fB .br \fP .SH DESCRIPTION .LP The \fImlockall\fP() function shall cause all of the pages mapped by the address space of a process to be memory-resident until unlocked or until the process exits or \fIexec\fPs another process image. The \fIflags\fP argument determines whether the pages to be locked are those currently mapped by the address space of the process, those that are mapped in the future, or both. The \fIflags\fP argument is constructed from the bitwise-inclusive OR of one or more of the following symbolic constants, defined in \fI\fP: .TP 7 MCL_CURRENT Lock all of the pages currently mapped into the address space of the process. .TP 7 MCL_FUTURE Lock all of the pages that become mapped into the address space of the process in the future, when those mappings are established. .sp .LP If MCL_FUTURE is specified, and the automatic locking of future mappings eventually causes the amount of locked memory to exceed the amount of available physical memory or any other implementation-defined limit, the behavior is implementation-defined. The manner in which the implementation informs the application of these situations is also implementation-defined. .LP The \fImunlockall\fP() function shall unlock all currently mapped pages of the address space of the process. Any pages that become mapped into the address space of the process after a call to \fImunlockall\fP() shall not be locked, unless there is an intervening call to \fImlockall\fP() specifying MCL_FUTURE or a subsequent call to \fImlockall\fP() specifying MCL_CURRENT. If pages mapped into the address space of the process are also mapped into the address spaces of other processes and are locked by those processes, the locks established by the other processes shall be unaffected by a call by this process to \fImunlockall\fP(). .LP Upon successful return from the \fImlockall\fP() function that specifies MCL_CURRENT, all currently mapped pages of the process' address space shall be memory-resident and locked. Upon return from the \fImunlockall\fP() function, all currently mapped pages of the process' address space shall be unlocked with respect to the process' address space. The memory residency of unlocked pages is unspecified. .LP The appropriate privilege is required to lock process memory with \fImlockall\fP(). .SH RETURN VALUE .LP Upon successful completion, the \fImlockall\fP() function shall return a value of zero. Otherwise, no additional memory shall be locked, and the function shall return a value of -1 and set \fIerrno\fP to indicate the error. The effect of failure of \fImlockall\fP() on previously existing locks in the address space is unspecified. .LP If it is supported by the implementation, the \fImunlockall\fP() function shall always return a value of zero. Otherwise, the function shall return a value of -1 and set \fIerrno\fP to indicate the error. .SH ERRORS .LP The \fImlockall\fP() function shall fail if: .TP 7 .B EAGAIN Some or all of the memory identified by the operation could not be locked when the call was made. .TP 7 .B EINVAL The \fIflags\fP argument is zero, or includes unimplemented flags. .sp .LP The \fImlockall\fP() function may fail if: .TP 7 .B ENOMEM Locking all of the pages currently mapped into the address space of the process would exceed an implementation-defined limit on the amount of memory that the process may lock. .TP 7 .B EPERM The calling process does not have the appropriate privilege to perform the requested operation. .sp .LP \fIThe following sections are informative.\fP .SH EXAMPLES .LP None. .SH APPLICATION USAGE .LP None. .SH RATIONALE .LP None. .SH FUTURE DIRECTIONS .LP None. .SH SEE ALSO .LP \fIexec\fP() , \fIexit\fP() , \fIfork\fP() , \fImlock\fP() , \fImunmap\fP() , the Base Definitions volume of IEEE\ Std\ 1003.1-2001, \fI\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 .