Commands using eval

Looks up a word on merriam-webster.com, does a screen scrape for the FIRST audio pronunciation and plays it.

USAGE: Put this one-liner into a shell script (e.g., ~/bin/pronounce) and run it from the command line giving it the word to say:

If the word isn't found in merriam-webster, no audio is played and the script returns an error value. However, M-W is a fairly complete dictionary (better than howjsay.com which won't let you hear how to pronounce naughty words).

ASSUMPTIONS: GNU's sed (which supports -r for extended regular expressions) and Linux's aplay. Aplay can be replaced by any program that can play .WAV files from stdin.

KNOWN BUGS: only the FIRST pronunciation is played, which is problematic if you wanted a particular form (plural, adjectival, etc) of the word. For example, if you run this:

you'll hear a voice saying "onomatopoeia".

Playing the correct form of the word is possible, but doing so might make the screen scraper even more fragile than it already is. (The slightest change to the format of m-w.com could break it).

When you start screen as `ssh-agent screen`, agent will die after detatch.

If you don't want to take care about files when stored agent's pid/socket/etc, you have to use this command.

It works as a method applicated to a variable, converts the string variable into an array

This command uses the top voted "Get your external IP" command from commandlinefu.com to get your external IP address.

Use this and you will always be using the communities favourite command.

This is a tongue-in-cheek entry and not recommended for actual usage.

Place the regular expression you want to validate between the forward slashes in the eval block.

It is not easy to make perl give a segfault, but this does it. This is a known issue but apparently not easy to fix. This is completely useless except for showing people that perl is not bullet-proof.

The coolest way I've found to backup a wordpress mysql database using encryption, and using local variables created directly from the wp-config.php file so that you don't have to type them- which would allow someone sniffing your terminal or viewing your shell history to see your info.

I use a variation of this for my servers that have hundreds of wordpress installs and databases by using a find command for the wp-config.php file and passing that through xargs to my function.

VARNAMES='ID FORENAME LASTNAME ADDRESS CITY PHONE MOBILE MAIL ...'

cat customer.csv | while read LINE ; do

COUNT=1

for VAR in $VARNAMES ; do

eval "${VAR}=`echo $LINE | /usr/bin/awk {'print $'$COUNT''}`"

let COUNT=COUNT+1

done

done

Maybe you have a CSV-File with addresses, where you have to process each contact (one per line, write each value to own variable). Of course you can define every variable, but this way is more simple and faster (to write).

VARNAMES includes the variable names. Pay attention: the number of names in VARNAMES have to be the same than in the CSV-file the fields. If the CSV is not seperated with ";", you can set the seperator after the awk-binary with -F"_" for example.

With this command you can use shell variables inside sed scripts.

This is useful if the script MUST remain in an external file, otherwise you can simply use an inline -e argument to sed.

If you put this in your .bashrc, you might also want to add this to make it use the colors by default: