Commands tagged file descriptor (4)

  • the tee command does fine with file names, but not so much with file descriptors, such as &2 (stderr). This uses process redirection to tee to the specified descriptor. In the sample output, it's being used to tee to stderr, which is connected with the terminal, and to wc -l, which is also outputting to the terminal. The result is the output of bash --version followed by the linecount Show Sample Output


    5
    tee >(cat - >&2)
    camocrazed · 2010-07-20 17:22:31 2
  • Sends both stdout and stderr to the pipe which captures the data in the file 'out.test' and sends to stdout of tee (likely /dev/tty unless redirected). Works on Bourne, Korn and Bash shells.


    4
    bash -x test.sh 2>&1 | tee out.test
    arcege · 2009-09-03 17:10:44 0
  • Description is moved to "Sample output" because the html sanitizer for commandlinefu breaks the examples.. Show Sample Output


    1
    diff rpm_output_from_other_computer <(rpm -qa|sort)
    xeor · 2011-06-25 11:45:15 0
  • Inner "ps...grep..." command searches for a process matching the specified . "lsof -p lists all file descriptors owned by . Includes open files, sockets, devices, etc... Show Sample Output


    0
    sudo lsof -p `sudo ps aux | grep -i neo4j | grep -v grep | awk '{ print $2 }'`
    andycunn · 2013-06-02 10:15:30 1

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Check your unread Gmail from the command line
Just an alternative with more advanced formating for readability purpose. It now uses colors (too much for me but it's a kind of proof-of-concept), and adjust columns.

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Convert seconds to [DD:][HH:]MM:SS
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Create a transition between two videos
We take the first 50 frames of a.mp4 for track a, and 24 blank frames followed by b.mp4 for track b. We then create a transition from track a to track b starting from frame 25 and ending at frame 49. The output is stored in out.mp4 To view the results without saving remove "-consumer avformat:out.mp4" from the end. Documentation of the mlt framework and the melt command can be found here: http://www.mltframework.org/bin/view/MLT/Documentation

Rename files in batch


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