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Diffstat (limited to 'man3p/mprotect.3p')
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diff --git a/man3p/mprotect.3p b/man3p/mprotect.3p new file mode 100644 index 000000000..06560e52c --- /dev/null +++ b/man3p/mprotect.3p @@ -0,0 +1,118 @@ +.\" Copyright (c) 2001-2003 The Open Group, All Rights Reserved +.TH "MPROTECT" P 2003 "IEEE/The Open Group" "POSIX Programmer's Manual" +.\" mprotect +.SH NAME +mprotect \- set protection of memory mapping +.SH SYNOPSIS +.LP +\fB#include <sys/mman.h> +.br +.sp +int mprotect(void *\fP\fIaddr\fP\fB, size_t\fP \fIlen\fP\fB, int\fP +\fIprot\fP\fB); \fP +\fB +.br +\fP +.SH DESCRIPTION +.LP +The \fImprotect\fP() function shall change the access protections +to be that specified by \fIprot\fP for those whole pages +containing any part of the address space of the process starting at +address \fIaddr\fP and continuing for \fIlen\fP bytes. The +parameter \fIprot\fP determines whether read, write, execute, or some +combination of accesses are permitted to the data being +mapped. The \fIprot\fP argument should be either PROT_NONE or the +bitwise-inclusive OR of one or more of PROT_READ, PROT_WRITE, +and PROT_EXEC. +.LP +If an implementation cannot support the combination of access types +specified by \fIprot\fP, the call to \fImprotect\fP() +shall fail. +.LP +An implementation may permit accesses other than those specified by +\fIprot\fP; however, no implementation shall permit a write +to succeed where PROT_WRITE has not been set or shall permit any access +where PROT_NONE alone has been set. Implementations shall +support at least the following values of \fIprot\fP: PROT_NONE, PROT_READ, +PROT_WRITE, and the bitwise-inclusive OR of PROT_READ +and PROT_WRITE. If PROT_WRITE is specified, the application shall +ensure that it has opened the mapped objects in the specified +address range with write permission, unless MAP_PRIVATE was specified +in the original mapping, regardless of whether the file +descriptors used to map the objects have since been closed. +.LP +The implementation shall require that \fIaddr\fP be a multiple of +the page size as returned by \fIsysconf\fP(). +.LP +The behavior of this function is unspecified if the mapping was not +established by a call to \fImmap\fP(). +.LP +When \fImprotect\fP() fails for reasons other than [EINVAL], the protections +on some of the pages in the range +[\fIaddr\fP,\fIaddr\fP+\fIlen\fP) may have been changed. +.SH RETURN VALUE +.LP +Upon successful completion, \fImprotect\fP() shall return 0; otherwise, +it shall return -1 and set \fIerrno\fP to indicate the +error. +.SH ERRORS +.LP +The \fImprotect\fP() function shall fail if: +.TP 7 +.B EACCES +The \fIprot\fP argument specifies a protection that violates the access +permission the process has to the underlying memory +object. +.TP 7 +.B EAGAIN +The \fIprot\fP argument specifies PROT_WRITE over a MAP_PRIVATE mapping +and there are insufficient memory resources to reserve +for locking the private page. +.TP 7 +.B EINVAL +The \fIaddr\fP argument is not a multiple of the page size as returned +by \fIsysconf\fP(). +.TP 7 +.B ENOMEM +Addresses in the range [\fIaddr\fP,\fIaddr\fP+\fIlen\fP) are invalid +for the address space of a process, or specify one or +more pages which are not mapped. +.TP 7 +.B ENOMEM +The \fIprot\fP argument specifies PROT_WRITE on a MAP_PRIVATE mapping, +and it would require more space than the system is able +to supply for locking the private pages, if required. +.TP 7 +.B ENOTSUP +The implementation does not support the combination of accesses requested +in the \fIprot\fP argument. +.sp +.LP +\fIThe following sections are informative.\fP +.SH EXAMPLES +.LP +None. +.SH APPLICATION USAGE +.LP +The [EINVAL] error above is marked EX because it is defined as an +optional error in the POSIX Realtime Extension. +.SH RATIONALE +.LP +None. +.SH FUTURE DIRECTIONS +.LP +None. +.SH SEE ALSO +.LP +\fImmap\fP() , \fIsysconf\fP() , the Base Definitions volume of +IEEE\ Std\ 1003.1-2001, \fI<sys/mman.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 . |