Commands by dubbaluga (1)

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Run a program transparently, but print a stack trace if it fails
For automated unit tests I wanted my program to run normally, but if it crashed, to add a stack trace to the output log. I came up with this command so I wouldn't have to mess around with core files. The one downside is that it does smoosh your program's stderr and stdout together.

Format date/time string for a different day
The "date' command has options to easily format the date, day, month, time, etc. But what if you want a relative date or time. Like, I wanted yesterday's date in a particular format. You may want the exact date of "2 months ago" or "-3 days" nicely formatted. For that, you can use this command. The --date option takes fuzzy parameters like the ones mentioned in the previous sentence.

List all open ports and their owning executables
Particularly useful on OS X where netstat doesn't have -p option.

Change string in many files at once and more.
Find all files that contain string XXX in them, change the string from XXX to YYY, make a backup copy of the file and save a list of files changed in /tmp/fileschanged.

Calculate days on which Friday the 13th occurs
Alter the years in the first brace expansion to select your year range. Modify date format to your liking but leave " %w" at the end.

Filter IP's in apache access logs based on use
Show's per IP of how many requests they did to the Apache webserver

Insert an element into xml
This inserts an element as last child under /breakfast_menu/food in simple.xml. xml used - http://www.w3schools.com/xml/simple.xml

Squish repeated delimiters into one
This can be particularly useful used in conjunction with a following cut command like $echo "hello::::there" | tr -s ':' | cut -d':' -f2 which prints 'there'. Much easier that guessing at -f values for cut. I know 'tr -s' is used in lots of commands here already but I just figured out the -s flag and thought it deserved to be highlighted :)

HDD Performance Write Test
Test your XFS filesystem and Raptor hard drives for write performance.

Output as many input
Output of a command as input to many


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