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MPROTECT(2) OpenBSD Programmer's Manual MPROTECT(2)
mprotect - control the protection of pages
mprotect(void *addr, size_t len, int prot);
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-
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.
Upon successful completion, a value of 0 is returned. Otherwise, a value
of -1 is returned and errno is set to indicate the error.
madvise(2), mincore(2), msync(2), munmap(2)
The mprotect() function first appeared in 4.4BSD.
OpenBSD 3.8 June 9, 1993 1