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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.
Creates a consistent datapumpt export on an Oracle database with the current sequence number, while the system is running and changes happens on the database.
Mostly for Norwegians, but easily adoptable to others. Very handy if you are brainstorming for a new domainname.
Will only display the available ones..
You can usually do this better with dig, but if you dont have dig, or the TLD only have an online service to check with, this will be usefull..
recently some in the #linux shared this. to find out the kernel version name from the binary without using uname
Log a command's votes,
gnuplot -persist <(echo "plot 'votes' with lines")
From Hong Kong Observatory wap site ;)
The ^$ within the quotes is a regular expression: ^=beginning of line, $=end of line, with no characters between.
You're behind on your TV catch-up, but how far behind? This command tries to open mplayer against all files in the current dir. If it's a video file it will contain ID_LENGTH, which is summed and output in hours, minutes and seconds.
Someone better at awk could probably reduce this down a lot.
Output is from Debian Lenny
This is how I typically grep. -R recurse into subdirectories, -n show line numbers of matches, -i ignore case, -s suppress "doesn't exist" and "can't read" messages, -I ignore binary files (technically, process them as having no matches, important for showing inverted results with -v)
I have grep aliased to "grep --color=auto" as well, but that's a matter of formatting not function.
Searches all files,dirs (also hidden) recursively
shorter typing with no need to use xargs.
List all text files in the current directory.
After executing this, click on a window you want to track X Window events in.
Explaination: "xev will track events in the window with the following -id, which we get by greping window information obtained by xwininfo"
Show apps that use internet connection at the moment.
Can be used to discover what programms create internet traffic. Skip the part after awk to get more details, though it will not work showing only unique processes.
This version will work with other languages such as Spanish and Portuguese, if the word for "ESTABLISHED" still contain the fragment "STAB"(e.g. "ESTABELECIDO")
This corrects duplicate output from the previous command.
Can be used to discover what programms create internet traffic. Skip the part after awk to get more details.
Has anyone an idea why the uniq doesn't work propperly here (see sample output)?
This is just for fun.
This obey that you don't match any broadcast or network addresses and stay between 220.127.116.11 - 254.254.254.254
regex to match an ip