lock user's system mailbox
lockspool is useful for a client mail program to attain
lockspool obtains a
username.lock for the calling user and retains it
until stdin is closed or a signal like
received. Additionally, the superuser may specify the name of a user in order
to lock a different mailbox.
lockspool is able to create the lock
file, “1” is written to stdout, otherwise “0” is
written and an error message is written to stderr.
lockspool will try up to 10 times to get the lock
(sleeping for a short period in between tries).
Typical usage is for a user mail agent (such as
mail(1)) to open a pipe to
lockspool when it needs to lock the user's mail
spool. Closing the pipe will cause
release the lock.
- user's mail lock file
lockspool utility exits 0 on success, and 1 if an
lockspool program appeared in