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If applicable, add the following below this CDDL HEADER, with the fields enclosed by brackets "[]" replaced with your own identifying information: Portions Copyright [yyyy] [name of copyright owner] .TH mprotect 2 "12 Jan 1998" "SunOS 5.11" "System Calls" .SH NAME mprotect \- set protection of memory mapping .SH SYNOPSIS .LP .nf #include \fBint\fR \fBmprotect\fR(\fBvoid *\fR\fIaddr\fR, \fBsize_t\fR \fIlen\fR, \fBint\fR \fIprot\fR); .fi .SH DESCRIPTION .sp .LP The \fBmprotect()\fR function changes the access protections on the mappings specified by the range [\fIaddr, addr + len\fR\|), rounding \fIlen\fR up to the next multiple of the page size as returned by \fBsysconf\fR(3C), to be that specified by \fIprot\fR. Legitimate values for \fIprot\fR are the same as those permitted for \fBmmap\fR(2) and are defined in <\fBsys/mman.h\fR> as: .sp .ne 2 .mk .na \fB\fBPROT_READ\fR\fR .ad .RS 14n .rt \fB/* page can be read */\fR .RE .sp .ne 2 .mk .na \fB\fBPROT_WRITE\fR\fR .ad .RS 14n .rt \fB/* page can be written */\fR .RE .sp .ne 2 .mk .na \fB\fBPROT_EXEC\fR\fR .ad .RS 14n .rt \fB/* page can be executed */\fR .RE .sp .ne 2 .mk .na \fB\fBPROT_NONE\fR\fR .ad .RS 14n .rt \fB/* page can not be accessed */\fR .RE .sp .LP When \fBmprotect()\fR fails for reasons other than \fBEINVAL\fR, the protections on some of the pages in the range [\fIaddr, addr + len\fR) may have been changed. If the error occurs on some page at \fIaddr2\fR, then the protections of all whole pages in the range [\fIaddr, addr2\fR] will have been modified. .SH RETURN VALUES .sp .LP Upon successful completion, \fBmprotect()\fR returns \fB0\fR. Otherwise, it returns \fB\(mi1\fR and sets \fBerrno\fR to indicate the error. .SH ERRORS .sp .LP The \fBmprotect()\fR function will fail if: .sp .ne 2 .mk .na \fB\fBEACCES\fR\fR .ad .RS 10n .rt The \fIprot\fR argument specifies a protection that violates the access permission the process has to the underlying memory object. .RE .sp .ne 2 .mk .na \fB\fBEINVAL\fR\fR .ad .RS 10n .rt The \fIlen\fR argument has a value equal to 0, or \fIaddr\fR is not a multiple of the page size as returned by \fBsysconf\fR(3C). .RE .sp .ne 2 .mk .na \fB\fBENOMEM\fR\fR .ad .RS 10n .rt Addresses in the range [\fIaddr, addr + len\fR) are invalid for the address space of a process, or specify one or more pages which are not mapped. .RE .sp .LP The \fBmprotect()\fR function may fail if: .sp .ne 2 .mk .na \fB\fBEAGAIN\fR\fR .ad .RS 10n .rt The address range [\fIaddr, addr + len\fR) includes one or more pages that have been locked in memory and that were mapped \fB\fR\fBMAP_PRIVATE\fR\fB;\fR \fIprot\fR includes \fB\fR\fBPROT_WRITE\fR\fB;\fR and the system has insufficient resources to reserve memory for the private pages that may be created. These private pages may be created by store operations in the now-writable address range. .RE .SH ATTRIBUTES .sp .LP See \fBattributes\fR(5) for descriptions of the following attributes: .sp .sp .TS tab() box; cw(2.75i) |cw(2.75i) lw(2.75i) |lw(2.75i) . \fBATTRIBUTE TYPE\fRATTRIBUTE VALUE _ Interface StabilityStandard .TE .SH SEE ALSO .sp .LP \fBmmap\fR(2), \fBplock\fR(3C), \fBmlock\fR(3C), \fBmlockall\fR(3C), \fBsysconf\fR(3C), \fBattributes\fR(5), \fBstandards\fR(5)