When a process accesses a file, it attempts to get a lock on the file so that it can have Write, as well as Read, access. (A process can be your Visual Effects and Finishing application or a remote application transferring media over Wire.) When a file is locked by one process, no other process can write to that file, which ensures that files do not get corrupted or accidentally overwritten by multiple users.

When a process finishes working on a file, it releases the lock so that other processes can get Write access. However, if the process is unable to release the file because of a problem, that lock file will remain and will prohibit other processes from getting a lock, even if the process is not using the file.

If you can't get Write access to a file, use the following procedure to locate the lock file and check to see if the file is legitimately locked. If the file is not locked by an active process, you can delete the lock file so that another process can get Write access.

To evaluate lock files:

1. Open the clip directory /usr/discreet/clip and locate the lock files:

   find . -name '*-lock'

   The command returns results similar to the following example:

   ./burnBat/SNA.clib-lock

   ./wiretap/Default.clib-lock

   This example indicates that there are two lock files.

2. Determine what processes have locked the files. Type:

   ls -l ./burnBat/SNA.clib-lock

   This command returns results similar to the following:

   lrwxrwxrwx 1 root users 19 Jun 15 09:14 ./burnBat/SNA.clib-lock -> 172.16.129.53:16488

   In this example, the IP address of the machine that is running the process and the ID of the process are provided at the end of the line. In this example, the IP address is 172.16.129.53 and the process ID is 16488.

3. To determine if that process is still running, log in to the machine where the process was running. Then use the ID to determine if the process is running. Type:

   ps -e | grep <process_ID>

   Using the process ID from the previous example, this command would look like:

   ps -e | grep 16488

   This command has two possible results:

   • If the command returns nothing, it indicates that the process is not running and the lock file is not necessary.

     After you have determined that no process has locked a file, you can delete the lock file.

   • If the command returns a process name, you know that a process is running and has locked the file. You can't delete the lock file without jeopardizing someone else's work.