Commands tagged stdout (10)

  • intercept stdout/stderr of another process


    59
    strace -ff -e trace=write -e write=1,2 -p SOME_PID
    oernii2 · 2010-04-20 08:55:54 11
  • intercept stdout/stderr of another process

    similar to the previous command, but with more friendly output (tested on linux)


    10
    strace -ff -e write=1,2 -s 1024 -p PID 2>&1 | grep "^ |" | cut -c11-60 | sed -e 's/ //g' | xxd -r -p
    systemj · 2010-04-23 16:22:17 4
  • Setting global redirection of STDERR to STDOUT in a script

    You have a script where =ALL= STDERR should be redirected to STDIN and you don't want to add "2>&1" at the end of each command... E.G.: ls -al /foo/bar 2>&1 Than just add this piece of code at the beginning of your script! I hope this can help someone. :)


    9
    exec 2>&1
    morgents · 2010-08-05 08:24:18 6
  • intercept stdout/stderr of another process or disowned process

    Useful to recover a output(stdout and stderr) "disown"ed or "nohup"ep process of other instance of ssh. With the others options the stdout / stderr is intercepted, but only the first n chars. This way we can recover ALL text of stdout or stderr Show Sample Output


    3
    strace -e write=1,2 -p $PID 2>&1 | sed -un "/^ |/p" | sed -ue "s/^.\{9\}\(.\{50\}\).\+/\1/g" -e 's/ //g' | xxd -r -p
    glaudiston · 2010-10-06 19:37:39 4
  • Redirect bash built-in output to stdout

    I've had a horrible time trying to pipe the output of some shell built-ins like 'time' to other programs. The built-in doesn't output to stdout or stderr most of the time but using the above will let you pipe the output to something else. Show Sample Output


    1
    TIME=$( { time YOUR_COMMAND_HERE; } 2>&1 ) ; echo $TIME
    allrightname · 2010-11-18 15:48:05 9
  • highlight chars or words in program output

    save as shell script and pipe your command output Show Sample Output


    0
    #!/bin/zsh SHL='\\e[0;31m' EHL='\\e[0m' while read line; do TEXT=$line for SSTR in $*; do TEXT=$(echo $TEXT | sed -e "s:$SSTR:${SHL}${SSTR}${EHL}:g") done echo -e $TEXT done
    steigr · 2012-06-06 12:57:50 3
  • Suppress standard output using > /dev/null

    This will be very helpful when you are debugging shell scripts, where you don?t want to display the echo statement and interested in only looking at the error messages. Similarly use 2> to supress error messages Show Sample Output


    0
    cat file.txt > /dev/null
    ankush108 · 2012-06-26 18:34:12 3
  • Copy to clipboard in addition to stdout (OSX).

    Very convenient to for sending data to the clipboard for processing. However, note that tee will affect the buffering of the output (stdout won't be update very live). Show Sample Output


    0
    alias t="tee >(pbcopy)"
    lgarron · 2014-01-24 12:41:07 9
  • Prepend text to stdout of running job

    Run a job in the background and prefix it's output with some string. This is particularly useful if you are running inside a docker container in a startup script (sue me, I'll run two jobs in a docker container if I want to) and you can run something like: /usr/sbin/nginx 2>&1 | awk '{print "[NGINX] " $0}' & /opt/jws-3.1/tomcat8/bin/catalina.sh run 2>&1 | awk '{print "[TOMCAT] " $0}' & while true; do ; done it can also be combined with tee to create a file log as well as a stdout log, for example if the script above where a script called "/bin/start-container.sh" then you could run /bin/start-container.sh | tee /var/log/containerlogs Show Sample Output


    0
    nginx 2>&1 | awk '{print "[NGINX] " $0}' &
    hvindin · 2017-04-25 22:18:38 20
  • Append output to the beginning of a file.

    Adds the stdout (standard output) to the beginning of logfile.txt. Change "command" to whatever command you like, such as 'ls' or 'date', etc. It does this by adding the output to a temporary file, then adding the previous contents of logfile.txt to the temp file, then copying the new contents back to the logfile.txt and removing the temp file.


    -2
    command > tmp && cat logfile.txt >> tmp && tmp > logfile.txt && rm tmp
    akoumjian · 2009-04-05 22:00:32 12

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