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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Create a bunch of dummy text files
Avoiding a for loop brought this time down to less than 3 seconds on my old machine. And just to be clear, 33554432 = 8192 * 4086.

Sets shell timeout
Useful in root's .profile - will auto-logout after TMOUT seconds of inactivity. Close after `seconds` inactive. export TMOUT=seconds (unefunge)

Find usb device in realtime
Using this command you can track a moment when usb device was attached.

Output a list of svn repository entities to xml file
I use this to pull the last commit date for everything in my repo, so I can tell the client which files haven't been touched or updated since the repo was created. Another way to do it is to use svn log, but that does not pull the "kind" attribute. It does, however, give you the commit message. Both are very useful.

Execute a command at a given time
This is an alternative to cron which allows a one-off task to be scheduled for a certain time.

Calculate days on which Friday the 13th occurs
I removed the dependency of the English language

urldecoding with one pure BASH builtin
You can use ordinary printf to convert "%23%21%2fbin%2fbash" into "#!/bin/bash" with no external utilities, by using a little known printf feature -- the "%b" specifier converts shell escapes. Replace % with \x and printf will understand the urlencoded string. BASH's printf has an extension to set a variable directly, too. So you get to convert urlencoded strings from garble to plaintext in one step with no externals and no backticks.

Get a list of ssh servers on the local subnet
Scan the local network for servers who have the ssh port open.

Lists installed kernels
no need for rpm, no need for piping to another command. also no real fu but lacking in unnecessary complexity and distro specific commands.

List all installed Debian packages
Should work on all systems that use dpkg and APT package management.

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