[H-GEN] ASCII Characters

[Michael Anthon]

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On Monday 27 October 2003 14:14, Greg Black wrote:
<snip>
>     for f in * ; do if grep foo < $f > /dev/null ; then echo $f ; fi ; done
<snip>

It might produce the same result but I suspect it is somewhat less efficient.  
With going to the effort of actually checking the source I will assume that 
the smart [1] people that added the -l option would have realised that once 
you find the pattern in a file there is no need to keep looking.  So, instead 
of telling you you are wrong we do a quick check of the man page and modify 
your method to...

for f in * ; do if grep -m 1 foo < $f > /dev/null ; then echo $f ; fi ; done

Still avoids -l (which I admit I use a fair bit) but without the performance 
hit of scanning all the files if there is no need.  To heda of the 
"processing power and RAM is cheap" crowd, consider that I have over 50G of 
text files on a netware file server that I occasionally need to grep through.  
I'm only able to access said files from my Win2k workstation (thank god for 
cygwin!)

Cheers,
Michael

[1]  I'm assuming they are smart, they keep telling us so...


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