plock(S)
plock --
lock process, text, or data in memory
Syntax
cc . . . -lc
#include <sys/lock.h>
int plock (op)
int op;
Description
The plock
system call 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
The plock system call
fails and does not perform the requested operation if one or more of
the following is true:
[EAGAIN]-
Not enough memory.
[EINVAL]-
-
op is equal to PROCLOCK
and a process lock, a text lock, or a data lock already
exists on the calling process.
-
op is equal to TXTLOCK and a text lock
or a process lock already exists on the calling process.
-
op is equal to DATLOCK
and a data lock or a process lock already exists on the calling
process.
-
op is equal to UNLOCK and no type of
lock exists on the calling process.
[EPERM]-
The effective user ID of the calling process is not super
user.
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.
See also
exec(S),
exit(S),
fork(S)
Standards conformance
plock is not part of any
currently supported standard;
it was developed by UNIX System Laboratories, Inc. and
maintained by The SCO Group.
© 2003 Caldera International, Inc. All rights reserved.
SCO OpenServer Release 5.0.7 -- 11 February 2003