Commands using exec (28)

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shell function to underline a given string.
underline() will print $1, followed by a series of '=' characters the width of $1. An optional second argument can be used to replace '=' with a given character. This function is useful for breaking lots of data emitted in a for loop into sections which are easier to parse visually. Let's say that 'xxxx' is a very common pattern occurring in a group of CSV files. You could run $ grep xxxx *.csv This would print the name of each csv file before each matching line, but the output would be hard to parse visually. $ for i in *.csv; do printf "\n"; underline $i; grep "xxxx" $i; done Will break the output into sections separated by the name of the file, underlined.

A rainbow-colored Tux gives a fortune cookie for the day. Great

Blackhole any level zones via dnsmasq
Explanation It creates dnsmasq-com-blackhole.conf file with one line to route all domains of com zones to You might use "address=/home.lab/" to point allpossiblesubdomains.home.lab to your localhost or some other IP in a cloud.

Go (cd) directly into a new temp folder
This command create a new temp directory using mktemp (to avoid collisions) and change the current working directory to the created directory.

finding cr-lf files aka dos files with ^M characters
Looking for carriage returns would also identify files with legacy mac line endings. To fix both types: $ perl -i -pe 's/\r\n?/\n/g' $(find . -type f -exec fgrep -l $'\r' "{}" \;)

back up your commandlinefu contributed commands
Use `zless` to read the content of your *rss.gz file: $ zless commandlinefu-contribs-backup-2009-08-10-07.40.39.rss.gz

Run remote web page, but don't save the results
I have a remote php file that I want to run once an hour. I set up cron to run this wget. I don't really care about what's in the file though, I don't want to save the results, so I run the -O and send it to /dev/null

validate the syntax of a perl-compatible regular expression
Place the regular expression you want to validate between the forward slashes in the eval block.

Quickly generate an MD5 hash for a text string using OpenSSL
Here Strings / A variant of here documents, the format is:

Merge files, joining each line in one line

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