MPROTECT(2) OpenBSD Programmer's Manual MPROTECT(2) NAME mprotect - control the protection of pages SYNOPSIS #include <sys/types.h> #include <sys/mman.h> int mprotect(void *addr, size_t len, int prot); DESCRIPTION The mprotect() system call changes the specified pages to have protection prot. Not all implementations will guarantee protection on a page basis; the granularity of protection changes may be as large as an entire re- gion. The protections (region accessibility) are specified in the prot argument by OR'ing the following values: PROT_EXEC Pages may be executed. PROT_READ Pages may be read. PROT_WRITE Pages may be written. PROT_NONE No permissions. RETURN VALUES Upon successful completion, a value of 0 is returned. Otherwise, a value of -1 is returned and errno is set to indicate the error. SEE ALSO madvise(2), mincore(2), msync(2), munmap(2) HISTORY The mprotect() function first appeared in 4.4BSD. OpenBSD 3.7 June 9, 1993 1