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Full Discussion: AWK Script and Commandline difference
Top Forums Shell Programming and Scripting AWK Script and Commandline difference Post 302535023 by Corona688 on Wednesday 29th of June 2011 11:37:21 AM
Old 06-29-2011
Quote:
Originally Posted by yazu
I wrote about quoting shell variables not about embedding.

Maybe you true about awk but the "pretty bad" way is universal
It's a bad idea because it becomes language syntax, not merely a string. This is especially bad for a variable, where you might not have strict control over the exact contents:
Code:
$ STR="hello 'world'"
$ awk 'BEGIN { print "'$STR'" }'
awk: BEGIN { print "hello
awk:               ^ unterminated string
$

Quote:
it's for perl
Code:
 VAR="this will barf'"
# subsitute in the shell and it barfs, taking the extra ' as perl syntax
$ perl -e "print '$VAR', "\n";'
Can't find string terminator '"' anywhere before EOF at -e line 1.
# do it properly and it will not.
$ perl -e 'print shift, "\n"' "$VAR"
this will barf'
$

Quote:
...sed, python or almost anything other, where you want to embed shell variables.
I admit there's no good way to do it in sed, but this is an argument against sed, not an argument for that syntax. It's very difficult to safely put variables in sed because so many things need escaping.

And if the argument is that you don't need to memorize syntax for each language, well, you already had to memorize -e for perl, how much harder is -v, shift, etc?
Last edited by Corona688; 06-29-2011 at 12:42 PM..
 

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LEARN ABOUT LINUX

igawk

IGAWK(1)							 Utility Commands							  IGAWK(1)

NAME

       igawk - gawk with include files

SYNOPSIS

       igawk [ all gawk options ] -f program-file [ -- ] file ...
       igawk [ all gawk options ] [ -- ] program-text file ...

DESCRIPTION

       Igawk is a simple shell script that adds the ability to have ``include files'' to gawk(1).

       AWK programs for igawk are the same as for gawk, except that, in addition, you may have lines like

	      @include getopt.awk

       in your program to include the file getopt.awk from either the current directory or one of the other directories in the search path.

OPTIONS

       See gawk(1) for a full description of the AWK language and the options that gawk supports.

EXAMPLES

       cat << EOF > test.awk
       @include getopt.awk

       BEGIN {
	    while (getopt(ARGC, ARGV, "am:q") != -1)
		 ...
       }
       EOF

       igawk -f test.awk

SEE ALSO

       gawk(1)

       Effective AWK Programming, Edition 1.0, published by the Free Software Foundation, 1995.

AUTHOR

       Arnold Robbins (arnold@skeeve.com).

Free Software Foundation					    Nov 3 1999								  IGAWK(1)
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