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Full Discussion: Odd(?) shell script practise
The Lounge What is on Your Mind? Odd(?) shell script practise Post 302803939 by verdepollo on Tuesday 7th of May 2013 05:13:38 PM
Old 05-07-2013
1) Yes, I've seen it a lot.
2) I'm not aware of such University either.

It's a matter of preference which in turn is driven by the known convention of capitalizing all environment variables and shell internal variables.

$CAT UUoC.txt | $GREP stuff | $CUT stuff is definitely more visible and less prone to confusion than $cat UUoC.txt | $grep stuff | $cut stuff.

It also helps when you want to throw a few extra flags into the command. Consider this for example:
Code:
SSH="$(which ssh) -o ConnectTimeout=4 -o UserKnownHostFile=stuff -o Port=12345 -o PermitLocalCommand=yes -o NoHostAuthenticationForLocalhost <...>"

I usually prefer GREP=$(which grep) or even GREP=$(which grep 2>/dev/null || echo :) if I want to be extra paranoid, but I only do this when writing shell scripts.

For compiled languages most people I know use #define kVariableName which seems to be pretty standard in C-based languages (I only use Obj-C though).
 

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LEARN ABOUT LINUX

gzgrep

GZGREP(1)						      General Commands Manual							 GZGREP(1)

NAME

       gzgrep, gzegrep, gzfgrep - search possibly compressed files for a regular expression

SYNOPSIS

       gzgrep [ grep_options ] [ -e ] pattern filename...

DESCRIPTION

       gzgrep is used to invoke the grep on compress'ed or gzip'ed files. All options specified are passed directly to grep.  If no file is speci-
       fied, then the standard input is decompressed if necessary and fed to grep.  Otherwise the given files are uncompressed	if  necessary  and
       fed to grep.

       If  gzgrep  is  invoked as gzegrep or gzfgrep then egrep or fgrep is used instead of grep.  If the GREP environment variable is set, gzgrep
       uses it as the grep program to be invoked. For example:

	   for sh:  GREP=fgrep	gzgrep string files
	   for csh: (setenv GREP fgrep; gzgrep string files)

AUTHOR

       Charles Levert (charles@comm.polymtl.ca)

SEE ALSO

       grep(1), egrep(1), fgrep(1), gzdiff(1), gzmore(1), gznew(1), gzforce(1), gzip(1), gzexe(1)

ATTRIBUTES

       See attributes(5) for descriptions of the following attributes:

       +--------------------+-----------------+
       |  ATTRIBUTE TYPE    | ATTRIBUTE VALUE |
       +--------------------+-----------------+
       |Availability	    | SUNWgzip	      |
       +--------------------+-----------------+
       |Interface Stability | External	      |
       +--------------------+-----------------+
NOTES

       Source for gzip is available in the SUNWgzipS package.

																	 GZGREP(1)
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