Commands tagged old kernel (2)

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Add all unversioned files to svn
No need for grep, let awk do the match. This will not behave properly if the filenames contains whitespace, which is awk's default field separator.

grep -v with multiple patterns.
That's what the sed command should've been, sorry.

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.

find files ignoring .svn and its decendents

save date and time for each command in history
Date-time format: YYYY-MM-DD HH:MM:SS

See loaded modules in apache
Easiest way to check which modules are loaded in apache.

files and directories in the last 1 hour
added alias in ~/.bashrc alias lf='find ./* -ctime -1 | xargs ls -ltr --color'

make sure you don't add large file to your repository

Maximum PNG compression with optipng, advpng, and advdef
optipng and advancecomp (for the the advpng and advdef tools) are the best FOSS tools for losslessly compressing PNGs. With the above tool chain, you can cut off as much as 20% off a PNG's file size.

Look up the definition of a word
A bash function might also be useful: $ dict() { curl dict://dict.org/d:$1; } Or if you want less verbose output: $ dict() { curl -s dict://dict.org/d:$1 | perl -ne 's/\r//; last if /^\.$/; print if /^151/../^250/'; }


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