PLOCK(2)                                                 PLOCK(2)



     NAME
          plock - lock process, text, or data in memory

     SYNOPSIS
          #include <sys/lock.h>

          int plock (op)
          int op;

     DESCRIPTION
          plock allows the calling process to lock its text segment
          (text lock), its data segment (data lock), or both its text
          and data segments (process lock) into memory.  Locked
          segments are immune to all routine swapping.  plock also
          allows these segments to be unlocked.  The effective user ID
          of the calling process must be super-user to use this call.
          Op specifies the following:

                  PROCLOCK -    lock text and data segments into
                                memory (process lock)

                  TXTLOCK -     lock text segment into memory (text
                                lock)

                  DATLOCK -     lock data segment into memory (data
                                lock)

                  UNLOCK -      remove locks

          plock will fail and not perform the requested operation if
          one or more of the following are true:

          [EPERM]        The effective user ID of the calling process
                         is not super-user.

          [EINVAL]       Op is equal to PROCLOCK and a process lock, a
                         text lock, or a data lock already exists on
                         the calling process.

          [EINVAL]       Op is equal to TXTLOCK and a text lock, or a
                         process lock already exists on the calling
                         process.

          [EINVAL]       Op is equal to DATLOCK and a data lock, or a
                         process lock already exists on the calling
                         process.

          [EINVAL]       Op is equal to UNLOCK and no type of lock
                         exists on the calling process.

          [EAGAIN]       Not enough memory.




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     PLOCK(2)                                                 PLOCK(2)



     SEE ALSO
          exec(2), exit(2), fork(2).

     DIAGNOSTICS
          Upon successful completion, a value of 0 is returned to the
          calling process.  Otherwise, a value of -1 is returned and
          errno is set to indicate the error.

     ORIGIN
          AT&T V.3













































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