Commands tagged file change (2)

  • Here's a way to wait for a file (a download, a logfile, etc) to stop changing, then do something. As written it will just return to the prompt, but you could add a "; echo DONE" or whatever at the end. This just compares the full output of "ls" every 10 seconds, and keeps going as long as that output has changed since the last interval. If the file is being appended to, the size will change, and if it's being modified without growing, the timestamp from the "--full-time" option will have changed. The output of just "ls -l" isn't sufficient since by default it doesn't show seconds, just minutes. Waiting for a file to stop changing is not a very elegant or reliable way to measure that some process is finished - if you know the process ID there are much better ways. This method will also give a false positive if the changes to the target file are delayed longer than the sleep interval for any reason (network timeouts, etc). But sometimes the process that is writing the file doesn't exit, rather it continues on doing something else, so this approach can be useful if you understand its limitations.


    2
    while [ "$(ls -l --full-time TargetFile)" != "$a" ] ; do a=$(ls -l --full-time TargetFile); sleep 10; done
    dmmst19 · 2015-05-09 03:19:49 11
  • This command monitors changes in the current folder structure (subfolders included) and files, and log it into a hidden file in the same folder, called `.file_changes_YYMMDD.log`. Modify the `--exclude` parameters to define what should be skipped. Show Sample Output


    2
    fswatch --exclude=.git/* --exclude=.settings --event-flags --event-flag-separator=\; -t -f '%Y-%m-%d %H:%M:%S' . >> ./.file_changes_$(date +"%Y-%m-%d" | sed s/-//g).log
    paulera · 2023-08-17 23:06:30 198

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