Shell tips and tricks

[Steven W. Orr]

On Thursday, Nov 1st 2007 at 11:50 -0000, quoth Ben Scott:

=>On 11/1/07, Steven W. Orr <steveo at syslang.net> wrote:
=>> FYI, bash does not have here-strings. perl does. python has something
=>> similar.
=>
=>  According to TFM, it does:
=>
=>http://www.gnu.org/software/bash/manual/bashref.html#SEC43

Sorry, They do have something that I wasn't thinking of.


echo Hello | grep Hello 

can be replaced by 

grep Hello <<< Hello

of course you could also have 

foo=Hello
grep Hello <<< "$foo"


=>
=>  I still don't get the point of them, but it says it has them.  :)
=>
=>> Speaking of envvars and variable interpolation, here's something to add
=>> to your .bash_profile
=>>
=>> PS4='+${0##*/} line $LINENO: '
=>
=>  Wanna just tell us what that means?   :-)

Instead of running

script

if you want to debug it, then set PS4 and then run

bash -x script


Much more civilizeder.

-- 
Time flies like the wind. Fruit flies like a banana. Stranger things have  .0.
happened but none stranger than this. Does your driver's license say Organ ..0
Donor?Black holes are where God divided by zero. Listen to me! We are all- 000
individuals! What if this weren't a hypothetical question?
steveo at syslang.net