mlock(3C)                        UNIX System V                        mlock(3C)


NAME
      mlock, munlock - lock (or unlock) pages in memory

SYNOPSIS
      #include <sys/types.h>
      int mlock(caddrt addr, sizet len);
      int munlock(caddrt addr, sizet len);

DESCRIPTION
      The function mlock uses the mappings established for the address range
      [addr, addr + len) to identify pages to be locked in memory.  The effect
      of mlock(addr, len) is equivalent to memcntl(addr, len, MCLOCK, 0, 0,
      0).

      munlock removes locks established with mlock.  The effect of
      munlock(addr, len) is equivalent to memcntl(addr, len, MCUNLOCK, 0, 0,
      0).

      Locks established with mlock are not inherited by a child process after a
      fork and are not nested.

SEE ALSO
      fork(2), memcntl(2), mmap(2), mlockall(3C), plock(2), sysconf(3C).

DIAGNOSTICS
      Upon successful completion, the functions mlock and munlock return 0;
      otherwise, they return -1 and set errno to indicate the error.

NOTES
      Use of mlock and munlock requires that the user have appropriate
      privileges.























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