Updated: 2022/Sep/29
Please read Privacy Policy. It's for your privacy.
MPROTECT(2) System Calls Manual MPROTECT(2) NAME mprotect - control the protection of pages LIBRARY Standard C Library (libc, -lc) SYNOPSIS #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 region. 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 Placeholder when requesting no access permission. 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. ERRORS [EACCES] A memory protection violation occurred. The PROT_EXEC flag was attempted on pages which belong to a file system mounted with the NOEXEC flag. The new protection is less restrictive than the protection originally set with mmap(2). PaX mprotect restrictions prohibit the requested protection. [EINVAL] An invalid memory range, or invalid parameters were provided. [ENOMEM] A resource shortage occurred while internally calling uvm_map_protect(9). SEE ALSO madvise(2), mincore(2), msync(2), munmap(2) HISTORY The mprotect function first appeared in SunOS 4.0 and subsequently 4.4BSD. NetBSD 10.99 September 8, 2019 NetBSD 10.99