NAME
ublock – lock a region in a shell script
SYNOPSIS
ublock -[bu] <filename>
DESCRIPTION
ublock is a shell locking function. This is used to restrict access to sections of shell scripts to one user at a time. It uses the semaphore features of Unix and creates a file called name.sem to control access.
ublock prints a process id on stdout. To unlock a section when processing is complete, the process should be killed.
FLAGS
FLAG | ARGUMENT | TYPE | DESCRIPTION |
---|---|---|---|
-b | pid of the lock process is written to stdout in native binary format. Some processes can read this directly and speed up the interlocking. | ||
-u | Remove the semaphore file created for locking. This effectively unlocks a function. |
ERRORS
EXAMPLE
pid=`ublock update` ... process things exclusively ... kill $pid ... other processes can work ...