Commands tagged grep (409)

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Backup all MySQL Databases to individual files
No need to loop when we have `xargs`. The sed command filters out the first line of `show databases` output, which is always "Database".

Which processes are listening on a specific port (e.g. port 80)
swap out "80" for your port of interest. Can use port number or named ports e.g. "http"

Press ctrl+r in a bash shell and type a few letters of a previous command
In the sample output, I pressed ctrl+r and typed the letters las. I can't imagine how much typing this has saved me.

Get the time since epoch
Get the time since epoch. Useful when working with commands and logs which use this format.

Have subversion ignore a file pattern in a directory
If you don't want to commit files to subversion, and don't want those file to show up when doing an "svn stat", this command is what you need

Print github url for the current url
Works for repos cloned via ssh or https.

Ping Twitter to check if you can connect
Returns a JSON object, by connecting to the 'test' endpoint of the Twitter API. Simplest way to check if you can connect to Twitter. Output also available in XML, use '/help/test.xml' for that

invoke MATLAB functions from command line
`-r script.m` also possible

FAST Search and Replace for Strings in all Files in Directory
I needed a way to search all files in a web directory that contained a certain string, and replace that string with another string. In the example, I am searching for "askapache" and replacing that string with "htaccess". I wanted this to happen as a cron job, and it was important that this happened as fast as possible while at the same time not hogging the CPU since the machine is a server. So this script uses the nice command to run the sh shell with the command, which makes the whole thing run with priority 19, meaning it won't hog CPU processing. And the -P5 option to the xargs command means it will run 5 separate grep and sed processes simultaneously, so this is much much faster than running a single grep or sed. You may want to do -P0 which is unlimited if you aren't worried about too many processes or if you don't have to deal with process killers in the bg. Also, the -m1 command to grep means stop grepping this file for matches after the first match, which also saves time.

synchronicity
The British Government entering in the Gregorian era.


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