Ubuntu manuals

Provided by: kernel-doc-2.4.27_2.4.27-12_all

NAME

       posix_lock_file -

SYNOPSIS

       int  posix_lock_file  (struct  file  *filp,  struct  file_lock *caller,
       unsigned int wait);

ARGUMENTS

       filp         The file to apply the lock to

       caller       The lock to be applied

       wait         1 to retry automatically, 0 to return -EAGAIN

DESCRIPTION

       Add a POSIX style lock to a file.  We  merge  adjacent  locks  whenever
       possible.  POSIX  locks  are  sorted  by  owner  task, then by starting
       address

KAI PETZKE WRITES

       To make freeing a lock much faster, we  keep  a  pointer  to  the  lock
       before  the  actual  one. But the real gain of the new coding was, that
       lock_it and unlock_it became one function.

TO ALL PURISTS

        Yes, I use a few goto’s. Just pass on to the next function.