Commands tagged ascii (32)

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Switch to a user with "nologin" shell
You need sudo privileges for this command. Replace username with actual username.

Write comments to your history.
A null operation with the name 'comment', allowing comments to be written to HISTFILE. Prepending '#' to a command will *not* write the command to the history file, although it will be available for the current session, thus '#' is not useful for keeping track of comments past the current session.

Copy stdin to your X11 buffer
Have you ever had to scp a file to your work machine in order to copy its contents to a mail? xclip can help you with that. It copies its stdin to the X11 buffer, so all you have to do is middle-click to paste the content of that looong file :)

determine if tcp port is open
for udp nmap -sU -p 80 hostname

climagic's New Year's Countdown clock
This is the 140 character long new year's countdown timer that was posted to the climagic account on twitter and identi.ca. There are saner ways of doing this of course, but probably none of those would fit. Uses the figlet command, but of course you can replace figlet with just echo if you want.

Rename files in batch

Restart command if it dies.
works well in crontab.

Merge several pdf files into a single file

Exclude inserting a table from a sql import
Starting with a large MySQL dump file (*.sql) remove any lines that have inserts for the specified table. Sometimes one or two tables are very large and uneeded, eg. log tables. To exclude multiple tables you can get fancy with sed, or just run the command again on subsequently generated files.

Limit the cpu usage of a process
Similar to `cpulimit`, although `prlimit` can be found shipped with recent util-linux. Example: limit CPU consumption to 10% for a math problem which ordinarily takes up 100% CPU: Before: $ bc -l


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