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Full Discussion: Space Symbolism
Top Forums UNIX for Dummies Questions & Answers Space Symbolism Post 302185829 by era on Wednesday 16th of April 2008 02:48:14 AM
Old 04-16-2008
If there is no space between the quotation marks then it's the empty string, with no characters in it.

To symbolize a space, put a space between the quotation marks.

You can play with "echo" and "cat -A" to see what happens. (Your cat might use a slightly different option character.)

Code:
vnix$ echo "" | cat -A
$
vnix$ echo " " | cat -A
 $

The $ shows the end of line, so you can tell whether or not there was any whitespace. Or just put something around it:

Code:
vnix$ echo ."".
..
vnix$ echo ." ".
. .

\" means a literal double quote, so -d \"" is a syntax error (literal double quote followed by opening string quote, but no closing string quote). -d " " with a space between should work; doesn't it work for you? Backslash followed by space (-d \ )should also work, without any quote marks at all.
 

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LEARN ABOUT SUNOS

gzegrep

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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