01-26-2004
file descriptors
i m trying to learn processes in unix and i've been reading this but i don't quite get it. its regarding file descriptors. : each is a part of file pointers, they point to another area. indexes into an Operating system maintained table called "file descriptor table". one table per process. may contain 20 entries called file pointers which point to an area of memory containing info about the opening of the file.
can someone comment on that, please!
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pipcrm(1) General Commands Manual pipcrm(1)
NAME
pipcrm - remove a POSIX message queue or a POSIX named semaphore
SYNOPSIS
[option]...
DESCRIPTION
The command removes one or more specified POSIX message queue or POSIX named semaphore.
Options
The identifiers are specified by the following options:
Unlinks the queue name from the message queue
specified by the argument, msqname. If there are no processes with existing open descriptors for the message queue,
the queue is destroyed. If one or more processes have the message queue open, the removal of the queue is postponed
until all descriptors for the queue have been closed.
Unlinks the semaphore name from the semaphore
specified by the argument, semname. If there are no processes with existing open descriptors for the semaphore, the
semaphore is destroyed. If one or more processes have the semaphore open, the removal of the semaphore is postponed
until all descriptors for the semaphore have been closed.
The details of the removals are described in mq_unlink(2), and sem_unlink(2). The names can be found by using (see pipcs(1)).
SEE ALSO
pipcs(1), mq_unlink(2), mq_open(2), mq_send(2), mq_receive(2), sem_unlink(2), sem_open(2), sem_wait(2), sem_post(2).
STANDARDS CONFORMANCE
pipcrm(1)