Commands by nullrouter (3)

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List the size (in human readable form) of all sub folders from the current location

Dump root ext3 fs over ssh
...can do similar w/ tar, dd, xfsdump, e2fsdump, etc.

Create a tar file with the current date in the name.

Remove several files with ease
Rather than typing out all 10 files, you can use brace expansion to do the trick for you. This is useful for backup files, numbered files, or any files with a repeating pattern. Gives more control than 'rm file*' as I might want to keep others around.

Execute a command with a timeout
In this example the command "somecommand" will be executed and sent a SIGALARM signal if it runs for more than 10 seconds. It uses the perl alarm function. It's not 100% accurate on timing, but close enough. I found this really useful when executing scripts and commands that I knew might hang E.g. ones that connect to services that might not be running. Importantly this can be used within a sequential script. The command will not release control until either the command completes or the timeout is hit.

Convert CSV to JSON
Replace 'csv_file.csv' with your filename.

for newbies, how to get one line info about all /bin programs
Get simple description on each file from /bin dir, in list form, usefull for newbies.

Mount a .iso file in UNIX/Linux
"-o loop" lets you use a file as a block device

Parallel mysql dump restore
this command works with one gziped file per table, and restore 4 tables in parallel.

Merge files, joining each line in one line
Merge files, joining line by line horizontally. Very useful when you have a lot of files where each line represents an info about an event and you want to join them into a single file where each line has all the info about the same event See the example for a better understanding


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