if [ -z "${BASH_VERSINFO}" ] || [ -z "${BASH_VERSINFO[0]}" ] || [ ${BASH_VERSINFO[0]} -lt 4 ]; then echo "This script requires Bash version >= 4"; exit 1; fi

Make sure your script runs with a minimum Bash version

If you use new features of a certain Bash version in your shell script, make sure that it actually runs with the required version.

0
By: hfs
2011-02-25 11:02:47

These Might Interest You

  • (Please see sample output for usage) script.bash is your script, which will be crypted to script.secure script.bash --> script.secure You can execute script.secure only if you know the password. If you die, your script dies with you. If you modify the startup line, be careful with the offset calculation of the crypted block (the XX string). Not difficult to make script editable (an offset-dd piped to a gpg -d piped to a vim - piped to a gpg -c directed to script.new ), but not enough space to do it on a one liner. Show Sample Output


    5
    echo "eval \"\$(dd if=\$0 bs=1 skip=XX 2>/dev/null|gpg -d 2>/dev/null)\"; exit" > script.secure; sed -i s:XX:$(stat -c%s script.secure): script.secure; gpg -c < script.bash >> script.secure; chmod +x script.secure
    rodolfoap · 2013-03-09 11:16:48 5
  • echo "ls" > script.bash; This is my script, a simple 'ls'. gpg -c script.bash; Here I encrypt and passord-protect my script. This creates file script.bash.gpg. cat script.bash.gpg | gpg -d --no-mdc-warning | bash Here I open file script.bash.gpg, decrypt it and execute it.


    -2
    echo "ls" > script.bash; gpg -c script.bash; cat script.bash.gpg | gpg -d --no-mdc-warning | bash
    betsubetsu · 2013-03-10 09:34:12 1
  • A wrapper around ssh to automatically provide logging and session handling. This function runs ssh, which runs screen, which runs script. . The logs and the screen session are stored on the server. This means you can leave a session running and re-attach to it later, or from another machine. . . Requirements: * Log sessions on a remote server * Transparent - nothing extra to type * No installation - nothing to copy to the server beforehand . Features: * Function wrapper delegating to ssh - so nothing to remember - uses .ssh/config as expected - passes your command line option to ssh * Self-contained: no scripts to install on the server * Uses screen(1), so is: - detachable - re-attachable - shareable * Records session using script(1) * Configurable log file location, which may contain variables or whitespace L="$HOME" # local variable L="\$HOME" # server variable L="some space" . Limitations: * Log dir/file may not contain '~' (which would require eval on the server) . . The sessions are named by the local user connecting to the server. Therefore if you detach and re-run the same command you will reconnect to your original session. If you want to connect/share another's session simply run: USER=bob ssh root@server . The command above is stripped down to an absolute minimum. A fully expanded and annotated version is available as a Gist (git pastebin): https://gist.github.com/flatcap/3c42326abeb1197ee714 . If you want to add timing info to script, change the command to: ssh(){ L="\$HOME/logs/$(date +%F_%H:%M)-$USER";/usr/bin/ssh -t "$@" "mkdir -p \"${L%/*}\";screen -xRRS $USER script --timing=\"$L-timing\" -f \"$L\"";} Show Sample Output


    3
    ssh(){ L="\$HOME/logs/$(date +%F_%H:%M)-$USER";/usr/bin/ssh -t "$@" "mkdir -p \"${L%/*}\";screen -xRRS $USER script -f \"$L\"";}
    flatcap · 2015-10-14 13:14:29 1

  • 25
    bash -x ./post_to_commandlinefu.sh
    nottings · 2009-02-25 19:10:21 7
  • (Please see sample output for usage) Use any script name (the read command gets it) and it will be encrypted with the extension .crypt, i.e.: myscript --> myscript.crypt You can execute myscript.crypt only if you know the password. If you die, your script dies with you. If you modify the startup line, be careful with the offset calculation of the crypted block (the XX string). Not difficult to make script editable (an offset-dd piped to a gpg -d piped to a vim - piped to a gpg -c directed to script.new ), but not enough space to do it on a one liner. Sorry for the chmod on parentheses, I dont like "-" at the end. Thanks flatcap for the subshell abbreviation to /dev/null Show Sample Output


    6
    read -p 'Script: ' S && C=$S.crypt H='eval "$((dd if=$0 bs=1 skip=//|gpg -d)2>/dev/null)"; exit;' && gpg -c<$S|cat >$C <(echo $H|sed s://:$(echo "$H"|wc -c):) - <(chmod +x $C)
    rodolfoap · 2013-03-10 08:59:45 9
  • This command runs your shell script in the background with no output of any kind, and it will remain running even after you logout.


    7
    nohup /bin/sh myscript.sh 1>&2 &>/dev/null 1>&2 &>/dev/null&
    AskApache · 2009-08-18 07:24:52 4

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