plock(2) — sys5



PLOCK(2)        DOMAIN/IX Reference Manual (SYS5)        PLOCK(2)



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

USAGE
     #include <sys/lock.h>

     int plock (op)
     int op;

DESCRIPTION
     This call is included only for completeness.  It is not
     operational on DOMAIN/IX systems.

     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 seg-
     ments are immune to all routine swapping.  Plock also allows
     these segments to be unlocked.  The calling process must
     have the effective user ID of the super-user.  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

ERRORS
     Plock will fail if one or more of the following is 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.



Printed 5/10/85                                           PLOCK-1



PLOCK(2)        DOMAIN/IX Reference Manual (SYS5)        PLOCK(2)



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

RELATED INFORMATION
     exec(2), exit(2), fork(2)
















































PLOCK-2                                           Printed 5/10/85

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