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2011-03-12 - Confoo 2011 presentation
Slides are available from the commandlinefu presentation at Confoo 2011: http://presentations.codeinthehole.com/confoo2011/
2011-01-04 - Moderation now required for new commands
To try and put and end to the spamming, new commands require moderation before they will appear on the site.
2010-12-27 - Apologies for not banning the trolls sooner
Have been away from the interwebs over Christmas. Will be more vigilant henceforth.
2010-09-24 - OAuth and pagination problems fixed
Apologies for the delay in getting Twitter's OAuth supported. Annoying pagination gremlin also fixed.

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Remove blank lines from a file

Terminal - Remove blank lines from a file
sed -i.bak '/^[[:space:]]*$/d' file_name
2009-04-07 11:32:06
User: Highwayman
Functions: sed
Remove blank lines from a file

Remove blank lines from files, even if some of the lines have whitespace (spaces, tabs, etc.). Also creates a .bak copy of the original file. Works on Mac also.

Thanks to those all those who left comments.

Know a better way?

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What others think

"sed -i '/^\ *$/d' file_name" does the same

Comment by prayer 315 weeks and 5 days ago

Following will remove spaces and comments

sed '/ *#/d; /^ *$/d' file_name
Comment by alperyilmaz 315 weeks and 5 days ago
sed -i '/^\s*$/d' file_name

eliminates blank lines or lines with whitespace (spaces, tabs, etc.)

Comment by daithif 315 weeks and 5 days ago

@daithif: Great job! However, your command only works on Linux (Ubuntu 8.10), but not on Mac OS X (I tested against Leopard 10.5.6). The following works on both:

sed -i.bak '/^[[:space:]]*$/d' file_name

It also makes a back up with the .bak extension.

Comment by haivu 315 weeks and 4 days ago

Your point of view

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