Commands by muradcsc (1)

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Compare a remote dir with a local dir
You can compare directories on two different remote hosts as well: $ diff -y

do a full file listing of every file found with locate

Generate SHA1 hash for each file in a list
All output is placed in file SHA1SUMS which you can later check with 'sha1sum --check'. Works on most Linux distros where 'sha1sum' is installed.

runs a bash script in debugging mode

execute your commands and avoid history records
$ secret_command;export HISTCONTROL= This will make "secret_command" not appear in "history" list.

What is my public IP-address?
alternative to $curl ifconfig.me for those that don't have curl

Find the package that installed a command

Add directory to $PATH if it's not already there
Sometimes in a script you want to make sure that a directory is in the path, and add it in if it's not already there. In this example, $dir contains the new directory you want to add to the path if it's not already present. There are multiple ways to do this, but this one is a nice clean shell-internal approach. I based it on http://stackoverflow.com/a/1397020. You can also do it using tr to separate the path into lines and grep -x to look for exact matches, like this: $ if ! $(echo "$PATH" | tr ":" "\n" | grep -qx "$dir") ; then PATH=$PATH:$dir ; fi which I got from http://stackoverflow.com/a/5048977. Or replace the "echo | tr" part with a shell parameter expansion, like $ if ! $(echo "${PATH//:/$'\n'}" | grep -qx "$dir") ; then PATH=$PATH:$dir ; fi which I got from http://www.commandlinefu.com/commands/view/3209/. There are also other more regex-y ways to do it, but I find the ones listed here easiest to follow. Note some of this is specific to the bash shell.

Sync MySQL Servers via secure SSH-tunnel
I wanted to keep a backup of my company database server on my local homeserver. After I found maatkit to sync databases, everything except security seemed fine. SSH takes care of that part.

Watch active calls on an Asterisk PBX
This handles when you have a single call or channel. Other commands will strip out the result if there is a single channel or call active because the output changes the noun to be singular instead of plural.


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