Commands by colemar (3)

  • Silent: anywait () { for pid in "$@"; do while kill -0 "$pid" >/dev/null 2>&1; do sleep 0.5; done; done } Prints dots: anywaitd () { for pid in "$@"; do while kill -0 "$pid" >/dev/null 2>&1; do sleep 0.5; echo -n '.'; done; done } Prints process ids: anywaitp () { for pid in "$@"; do while kill -0 "$pid" >/dev/null 2>&1; do sleep 0.5; echo -n $pid' '; done; echo; done } You cannot anywait for other users processes. Show Sample Output

    wait 536; anywait 536; anywaitd 537; anywaitp 5562 5563 5564
    colemar · 2014-10-22 06:31:47 0
  • Define alias for convenience: alias clbin='curl -v -F "clbin=<-"' Paste man page: man bash | clbin Paste image: curl -F 'clbin=@filename.jpg'

    <command> | curl -F 'clbin=<-'
    colemar · 2014-10-21 13:02:18 4
  • Mirror a remote directory using some tricks to maximize network speed. lftp:: coolest file transfer tool ever -u: username and password (pwd is merely a placeholder if you have ~/.ssh/id_rsa) -e: execute internal lftp commands set sftp:connect-program: use some specific command instead of plain ssh ssh:: -a -x -T: disable useless things -c arcfour: use the most efficient cipher specification -o Compression=no: disable compression to save CPU mirror: copy remote dir subtree to local dir -v: be verbose (cool progress bar and speed meter, one for each file in parallel) -c: continue interrupted file transfers if possible --loop: repeat mirror until no differences found --use-pget-n=3: transfer each file with 3 independent parallel TCP connections -P 2: transfer 2 files in parallel (totalling 6 TCP connections) sftp://remotehost:22: use sftp protocol on port 22 (you can give any other port if appropriate) You can play with values for --use-pget-n and/or -P to achieve maximum speed depending on the particular network. If the files are compressible removing "-o Compression=n" can be beneficial. Better create an alias for the command. Show Sample Output

    lftp -u user,pwd -e "set sftp:connect-program 'ssh -a -x -T -c arcfour -o Compression=no'; mirror -v -c --loop --use-pget-n=3 -P 2 /remote/dir/ /local/dir/; quit" sftp://remotehost:22
    colemar · 2014-10-17 00:29:34 0

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Get AWS temporary credentials ready to export based on a MFA virtual appliance
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The scene in the Shining (Stanley Kubrick)
Let's take a rest. How about watch a horror? The Shining

Backup your LDAP
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Detect illegal access to kernel space, potentially useful for Meltdown detection
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dd with progress bar and statistics
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Scan all open ports without any required program

Kill a broken ssh connection
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zsh suffix to inform you about long command ending
make, find and a lot of other programs can take a lot of time. And can do not. Supppose you write a long, complicated command and wonder if it will be done in 3 seconds or 20 minutes. Just add "R" (without quotes) suffix to it and you can do other things: zsh will inform you when you can see the results. You can replace zenity with other X Window dialogs program.

"Pretty print" $PATH, show directories in $PATH, one per line with replacement pattern using shell parameter expansion
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Generate random valid mac addresses
First set the variable $hexchars: $hexchars="0123456789ABCDEF" Change the number in the first for loop if you need less then 1200 mac addresses

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