plock(2)                            CLIX                            plock(2)



  NAME

    plock - Locks process, text, or data in memory

  LIBRARY

    Standard C Library (libc.a)

  SYNOPSIS

    #include <sys/lock.h>

    int plock(
      int op );

  PARAMETERS

    op   Specifies the process segment to lock.

  DESCRIPTION

    The plock() function 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.  The plock() function also allows these segments to be
    unlocked.  The effective user ID of the calling process must be superuser
    to use this function.  The op parameter 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.

  EXAMPLES

    To lock text and data segments into memory:

    plock(PROCLOCK);


  RETURN VALUES

    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.

  ERRORS




  2/94 - Intergraph Corporation                                              1

  plock(2)                            CLIX                            plock(2)



    The plock() function fails and does 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 superuser.

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

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

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

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

    [EAGAIN]   Not enough memory.

  RELATED INFORMATION

    Functions:  exec(2), exit(2), fork(2)
































  2                                              Intergraph Corporation - 2/94