Login or Register to Ask a Question and Join Our Community

Sponsored Content
Full Discussion: grep -v while loop
Top Forums UNIX for Dummies Questions & Answers grep -v while loop Post 302104583 by reborg on Thursday 25th of January 2007 09:28:23 PM
Old 01-25-2007
Quote:
Originally Posted by bobo
alist contain:
a
b
c
d
e

blist contain:
a
b
c

the code:

#!/usr/bin/ksh
cat blist | while read line
do
grep -V "$line" alist > data
done

I expect to get

d
e

for my result but I don't. What is wrong?
I would expect you output to be:
b
c
d
e
f
a
c
d
e
f
a
b
d
e

and have no Idea why you are doing something so convoluted, since you appear to be attempting to replicate the behaviour of fgrep -v (or grep -vf)
 

10 More Discussions You Might Find Interesting

1. Shell Programming and Scripting

grep in a loop

Hi , I am trying a script which takes user input userid . I am stuck how to check whether that is a valid user id or not in the audit log files. My code is : cd $CCP_AUDIT cat * > /export/home/$USR/l***/files echo "UserId:\c" read UserId #Date Function echo "DATE : \c" read xxx I... (7 Replies)
Discussion started by: gundu
7 Replies

2. Shell Programming and Scripting

Grep commands in loop

Hi All, Reference to my previous post I need to compare all the lines in the file1 with file2 for this condition if file1 {$3,$5} ==file2 {$3,$5} then grep file2{$1}latest date. need output in file3 10/04/2008 09/04/2008 09/04/2008 08/04/2008 can anyone suggest me Thanks... (0 Replies)
Discussion started by: karthikn7974
0 Replies

3. Shell Programming and Scripting

Help with grep inside an if loop

Hello All, I have been reading posts on here for a while, but this is my first post. I have a document in which many sentences appear, and I am piping it through an exterior script which will tag each word in the document with its part of speech (not part of my script, just background). The... (3 Replies)
Discussion started by: daf189
3 Replies

4. Shell Programming and Scripting

Using grep within a while loop

Hi all, I have the below script to get input but i cannot get grep to work. input1.txt AAAAAAAAG input2.txt >gi|184009.1| LEAFY-like |AAAAAAAAGSGGGDHLPY However, when i use grep -f input1.txt input2.txt i cannot get any output matches (note that the match is underlined). Is it... (8 Replies)
Discussion started by: turkishvan
8 Replies

5. UNIX for Dummies Questions & Answers

grep sed and a loop

:wall: I have a requirement to search a log file that never rotates for certain values. If I find them I pipe them to a another file. To log file is constanyl being appened with new lines and never rotating Easy so far. The problem is I dont want to pipe out matches already seen before. ... (3 Replies)
Discussion started by: gunnahafta
3 Replies

6. Shell Programming and Scripting

Help on grep in a do while loop

So this is what I'm trying to do: I have a file called registry.txt which has a list of registry entries I want to search for. I have another file called inctrl.txt on which I want to perform the search on. Here's the example contents of registry.txt SOFTWARE\Microsoft\Security... (3 Replies)
Discussion started by: r4v3n
3 Replies

7. Red Hat

using grep in a while loop

Hello everybody, I have been searching it, but it seems I am unable to find the correct information, that s why I am asking you guys, hoping somebody get an idea. Here is my problem : I want a script to loop until a string is identified in a log file. Here is the script : #!/bin/sh... (5 Replies)
Discussion started by: guyiom
5 Replies

8. Homework & Coursework Questions

GREP loop

Use and complete the template provided. The entire template must be completed. If you don't, your post may be deleted! 1. The problem statement, all variables and given/known data: I need to search through the users home directories for keywords, display them. The code listed below will show... (7 Replies)
Discussion started by: jcllns1
7 Replies

9. UNIX for Beginners Questions & Answers

Grep command in a loop

Hello - I am running a script that is outputting to a log. Let call it output.log I would like to monitor that log until the line "Build Successful" is found. I think I would need to use the grep command. How would I do that in a loop? Thanks Marty (1 Reply)
Discussion started by: MSpeare
1 Replies

10. Shell Programming and Scripting

Ps ax with grep in loop

Hello, I have built the following script to check if processes supplied by the argument are running or not. #!/bin/bash PROCLIST=$1 PROCESS="0" ERROR_PROCS="" IFS='+' read -ra ADDR <<< "$PROCLIST" for PROC in "${ADDR}"; do if ; then PROCESS=1 ... (9 Replies)
Discussion started by: nms
9 Replies

LEARN ABOUT OPENSOLARIS

fgrep

fgrep(1)							   User Commands							  fgrep(1)

NAME

       fgrep - search a file for a fixed-character string

SYNOPSIS

       /usr/bin/fgrep [-bchilnsvx] -e pattern_list [file...]

       /usr/bin/fgrep [-bchilnsvx] -f file [file...]

       /usr/bin/fgrep [-bchilnsvx] pattern [file...]

       /usr/xpg4/bin/fgrep [-bchilnqsvx] -e pattern_list [-f file]
	    [file...]

       /usr/xpg4/bin/fgrep [-bchilnqsvx] [-e pattern_list] -f file
	    [file...]

       /usr/xpg4/bin/fgrep [-bchilnqsvx] pattern [file...]

DESCRIPTION

       The  fgrep (fast grep) utility searches files for a character string and prints all lines that contain that string. fgrep is different from
       grep(1) and from egrep(1) because it searches for a string, instead of searching for a pattern that matches an  expression.  fgrep  uses  a
       fast and compact algorithm.

       The characters $, *, [, ^, |, (, ), and  are interpreted literally by fgrep, that is, fgrep does not recognize full regular expressions as
       does egrep. These characters have special meaning to the shell. Therefore, to be safe, enclose the entire string within single quotes (a').

       If no files are specified, fgrep assumes standard input. Normally, each line that is found is copied to the standard output. The file  name
       is printed before each line that is found if there is more than one input file.

OPTIONS

       The following options are supported for both /usr/bin/fgrep and /usr/xpg4/bin/fgrep:

       -b		  Precedes each line by the block number on which the line was found. This can be useful in locating block numbers by con-
			  text. The first block is 0.

       -c		  Prints only a count of the lines that contain the pattern.

       -e pattern_list	  Searches for a string in pattern-list. This is useful when the string begins with a -.

       -f pattern-file	  Takes the list of patterns from pattern-file.

       -h		  Suppresses printing of files when searching multiple files.

       -i		  Ignores upper/lower case distinction during comparisons.

       -l		  Prints the names of files with matching lines once, separated by new-lines. Does not repeat the names of files when  the
			  pattern is found more than once.

       -n		  Precedes each line by its line number in the file. The first line is 1.

       -s		  Works silently, that is, displays nothing except error messages. This is useful for checking the error status.

       -v		  Prints all lines except those that contain the pattern.

       -x		  Prints only lines that are matched entirely.

   /usr/xpg4/bin/fgrep
       The following options are supported for /usr/xpg4/bin/fgrep only:

       -q    Quiet.  Does  not	write  anything  to  the standard output, regardless of matching lines. Exits with zero status if an input line is
	     selected.

OPERANDS

       The following operands are supported:

       file    Specifies a path name of a file to be searched for the patterns. If no file operands are specified,  the  standard  input  will	be
	       used.

   /usr/bin/fgrep
       pattern	  Specifies a pattern to be used during the search for input.

   /usr/xpg4/bin/fgrep
       pattern	  Specifies  one  or  more  patterns to be used during the search for input. This operand is treated as if it were specified as -e
		  pattern_list.

USAGE

       See largefile(5) for the description of the behavior of fgrep when encountering files greater than or equal to 2 Gbyte ( 2^31 bytes).

ENVIRONMENT VARIABLES

       See environ(5) for descriptions of the following environment variables that affect the execution of fgrep:  LC_COLLATE,	LC_CTYPE,  LC_MES-
       SAGES, and NLSPATH.

EXIT STATUS

       The following exit values are returned:

       0    If any matches are found

       1    If no matches are found

       2    For syntax errors or inaccessible files, even if matches were found.

ATTRIBUTES

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

   /usr/bin/fgrep
       +-----------------------------+-----------------------------+
       |      ATTRIBUTE TYPE	     |	    ATTRIBUTE VALUE	   |
       +-----------------------------+-----------------------------+
       |Availability		     |SUNWcsu			   |
       +-----------------------------+-----------------------------+

   /usr/xpg4/bin/fgrep
       +-----------------------------+-----------------------------+
       |      ATTRIBUTE TYPE	     |	    ATTRIBUTE VALUE	   |
       +-----------------------------+-----------------------------+
       |Availability		     |SUNWxcu4			   |
       +-----------------------------+-----------------------------+
       |CSI			     |Enabled			   |
       +-----------------------------+-----------------------------+

SEE ALSO

       ed(1), egrep(1), grep(1), sed(1), sh(1), attributes(5), environ(5), largefile(5), XPG4(5)

NOTES

       Ideally, there should be only one grep command, but there is not a single algorithm that spans a wide enough range of space-time tradeoffs.

       Lines are limited only by the size of the available virtual memory.

   /usr/xpg4/bin/fgrep
       The  /usr/xpg4/bin/fgrep  utility  is identical to /usr/xpg4/bin/grep -F (see grep(1)). Portable applications should use /usr/xpg4/bin/grep
       -F.

SunOS 5.11							    24 Mar 2006 							  fgrep(1)
All times are GMT -4. The time now is 07:22 PM.
Unix & Linux Forums Content Copyright 1993-2022. All Rights Reserved.
Privacy Policy