Login or Register to Ask a Question and Join Our Community

Sponsored Content
Full Discussion: grep backreferencing question
Top Forums Shell Programming and Scripting grep backreferencing question Post 302464256 by prasanna1157 on Tuesday 19th of October 2010 03:12:08 PM
Old 10-19-2010
grep backreferencing question
Quote:
Originally Posted by Scrutinizer
That wasn't part of your problem statement, was it? Anyway,
Code:
grep -E 'int .*([^,]+),.*\1[,\;]|int .*,[,\;]' infile

Code:
grep 'int .*\([^,][^,]*\),.*\1[,\;]\|int .*,[,\;]' infile


To be clear:

int a123,b,c; --- legal
int 12a,b; ---- illegal since the variable starts with a number
int A,b,c ---- illegal since the variable starts with [A-Z]


A few valid lines that should match (only when a variable occurs more than once):

int a,b,a;
int a,b,b;
int a,b,c,a,g;

---------- Post updated at 03:12 PM ---------- Previous update was at 03:07 PM ----------
Quote:
Originally Posted by DGPickett
Wrong comes in so many flavors, like integral calculus. Even right has a lot of flavors. First there are the datatypes, then the commas, the initializations, typedefs, unions, structs, Classes, code, continued lines, includes, macros.

Why not cc -c ? I hope it knows enough to catch that. There may even be c verification tools out there. Ever try lint?

Oh.. But it matches something like:

int aa; --- which should not match.
 

10 More Discussions You Might Find Interesting

1. UNIX for Dummies Questions & Answers

grep question

what is the format for grep if I want to search from the current directory and through all its subdirectories?:) (3 Replies)
Discussion started by: pkappaz
3 Replies

2. Shell Programming and Scripting

grep question

Hi, I am currently using grep -c to scan lines for certain data. I am just wondering if you can search a specific column of a file using grep -c. Thanks (6 Replies)
Discussion started by: Jaken
6 Replies

3. Shell Programming and Scripting

Grep question

I'm using grep in a shell and I was wondering: Can I grep a file and then delete all files that contain what it returns? So instead of grep 'blah' * and I have 50 files that have blah in it and I would have to delete all 50 manually, how would I just delete them all in one fell swoop? (3 Replies)
Discussion started by: tphegley
3 Replies

4. UNIX for Dummies Questions & Answers

Grep question.

Hi, I am executing the below command. grep ".UPDATE" file1.txt | grep -v MQQUEUE > Myprog1 The expected output is all lines in file1.txt which have the string ".UPDATE" and dont contain the string MQQUEUE. However, the output which I am getting is just searching for the string... (3 Replies)
Discussion started by: saurabhsinha23
3 Replies

5. Programming

'Backreferencing' in SQL?

My SQL is very rust and I'm having a problem with a query. First, here are the tables involved. Table `os`: +--------------------------------+ | id | distro | version | +--------------------------------+ | 1 | CentOS | 5.2 | | 2 | RHEL | 5 | | 3 ... (1 Reply)
Discussion started by: Housni
1 Replies

6. UNIX for Dummies Questions & Answers

grep question

Instead of using the following command #dmesg | grep -v sendmail | grep -v xntpd How can I use just one grep -v and give both arguments. Please suggest thanks (4 Replies)
Discussion started by: Tirmazi
4 Replies

7. Shell Programming and Scripting

grep question

Hello, Is there a way in grep to remember patterns? For eg: int a,b,c,d,a; If a variable is declared twice, like in the previous example, I should be able to print only those lines. Is there a way to print only the lines where the variable name occurs more than once, using grep... (1 Reply)
Discussion started by: prasanna1157
1 Replies

8. Shell Programming and Scripting

Grep question

All, I am wanting to find out if I can do this in one grep statement grep -R failed * |grep -iEw 'Mar 1|Feb 2' I want to search all files in a directory for the text "failed" AND a "date or date". Currently, I am using the above running one grep and then piping it to another. It works,... (3 Replies)
Discussion started by: markdjones82
3 Replies

9. Shell Programming and Scripting

Question about grep

can anyone tell me what the \/$ means? from grep \/$ (8 Replies)
Discussion started by: Nick1097
8 Replies

10. Shell Programming and Scripting

Question about grep

is there anyway i can ask grep to only get the first line? as in the top command line line 1 <-- just grep this line line 2 line 3 ---------- Post updated at 04:24 PM ---------- Previous update was at 04:19 PM ---------- nvm.. found out that i can do it with |head (12 Replies)
Discussion started by: Nick1097
12 Replies

LEARN ABOUT V7

zgrep

ZGREP(1)						      General Commands Manual							  ZGREP(1)

NAME

       zgrep - search possibly compressed files for a regular expression

SYNOPSIS

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

DESCRIPTION

       Zgrep  invokes  grep  on  compressed  or  gzipped  files.   These  grep	options  will  cause  zgrep  to  terminate  with  an  error  code:
       (-[drRzZ]|--di*|--exc*|--inc*|--rec*|--nu*).  All other options specified are passed directly to grep.  If no file is specified,  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 the GREP environment variable is set, zgrep uses it as the grep program to be invoked.

EXIT CODE

       2 - An option that is not supported was specified.

AUTHOR

       Charles Levert (charles@comm.polymtl.ca)

SEE ALSO

       grep(1), gzexe(1), gzip(1), zdiff(1), zforce(1), zmore(1), znew(1)

																	  ZGREP(1)
All times are GMT -4. The time now is 01:18 PM.
Unix & Linux Forums Content Copyright 1993-2022. All Rights Reserved.
Privacy Policy