System Calls Manual
NAME munmap — remove a mapping
LIBRARY Standard C Library (libc, -lc)
SYNOPSIS #include <sys/mman.h>
munmap(void *addr, size_t len);
DESCRIPTION The munmap() system call deletes the mappings for the specified address range, and causes further references to addresses within the range to generate invalid memory references.
RETURN VALUES Upon successful completion, munmap returns zero. Otherwise, a value of -1 is returned and errno is set to indicate the error.
() will fail if:
The addr parameter was not page aligned, or some part of the region being unmapped is outside the valid address range for a process.
STANDARDS The munmap() function conforms to IEEE Std 1003.1b-1993 (“POSIX.1b”).
HISTORY The munmap() function first appeared in 4.4BSD.