= NAME =
concurrent_check

= SYNOPSIS =
concurrent_check

= DESCRIPTION =
This function is used to prevent multiple tests from using the build area
for a test concurrently. It is called by the [[function_pre_build|pre_build]] function.

concurrent_check uses a local file as a build lock.  The lock file (while it exists during the execution of the test) hold the value of BUILD_URL.
If the lock file is present when function is entered, concurrent_check will
enter a while loop querying the jenkins server about the status of the job.
concurrent_check will wait in this loop until Jenkins reports that the job
has finished.

When concurrent_check exits, the lock file will be created, with the value
of build_url.  This lockfile is removed after the software from the build
area has been deployed to the target, by the [[function_post_deploy|post_deploy]] function.

= EXAMPLES =
Here are some sample invocations:
{{{#!YellowBox
concurrent_check
}}}

= ENVIRONMENT and ARGUMENTS =
The following environment variables are used by this function:
 * TRIPLET - defined in common.sh as ${JOB_NAME}-$PLATFORM
 * WORKSPACE
 * BUILD_URL

This function takes no positional arguments.

= RETURN =
Returns non-zero on error.  

= SOURCE =
Located in ''scripts/functions.sh''

= SEE ALSO =
 * [[function_post_deploy|post_deploy]]