Login or Register to Ask a Question and Join Our Community


Shell Programming and Scripting

Confusion with Reg expression

Login to Discuss or Reply to this Discussion in Our Community

 
Thread Tools Search this Thread
Top Forums Shell Programming and Scripting Confusion with Reg expression
# 1  
Old 06-13-2013
Question Confusion with Reg expression
I want to make a REG Expression to validate the directory.
my dirsample is below:
Code:
/abc/abc/abc
abc/abc/abc
abc/abc/abc/
/abc/a bc/abc
/a bc/abc/abc
/abc/abc/a bc
/ abc/abc/abc
/abc/ abc/abc
/abc/.abc
/.abc/abc
/
//
/abc
/.abc

And my code is below:
Code:
grep -E '^\/([0-9a-Z_-.]+\/?)+$' dirsample

And the result is below:
Code:
/abc/abc/abc
/abc/.abc
/.abc/abc
//
/abc
/.abc

However, I think one of the result "//" shouldn't appear because at least one digit or alphabet or special symbol ( _-. ) is supposed to follow the first "/" . So I don't know what's wrong.
Please give me some directions.
THX
Last edited by Scott; 06-13-2013 at 01:24 PM.. Reason: Code tags for code and data
# 2  
Old 06-13-2013
Code:
$ grep "/[^/]" file
/abc/abc/abc
abc/abc/abc
abc/abc/abc/
/abc/a bc/abc
/a bc/abc/abc
/abc/abc/a bc
/ abc/abc/abc
/abc/ abc/abc
/abc/.abc
/.abc/abc
/abc
/.abc

You can add more "invalid" characters in the [...] set, as you like.

If you want to validate the existence of these directories, then you can run that through a loop.
# 3  
Old 06-13-2013
Quote:
Originally Posted by Scott
Code:
$ grep "/[^/]" file
/abc/abc/abc
abc/abc/abc
abc/abc/abc/
/abc/a bc/abc
/a bc/abc/abc
/abc/abc/a bc
/ abc/abc/abc
/abc/ abc/abc
/abc/.abc
/.abc/abc
/abc
/.abc

Yes, your code is simple. However, it's not good if the absolute path of directory contains metacharacters. So I just did my best to avoid it happened.
# 4  
Old 06-13-2013
Quote:
Originally Posted by franksunnn
... or special symbol ( _-. )
That component of your regexp specifies a range, not three literal characters. The dash must appear first or last in the entire bracketed expression.

Regards,
Alister
# 5  
Old 06-13-2013
Quote:
Originally Posted by alister
That component of your regexp specifies a range, not three literal characters. The dash must appear first or last in the entire bracketed expression.

Regards,
Alister
OMG!
I got you! Thanks
Login or Register to Ask a Question

Previous Thread | Next Thread

10 More Discussions You Might Find Interesting

1. Shell Programming and Scripting

REG Expression

Need your help in creating regular expression for particular set. let say I have given two dates 20130623 to 20140625. I need to create regular for the dates which fall in between above two dates. (4 Replies)
Discussion started by: gvkumar25
4 Replies

2. Shell Programming and Scripting

reg expression in perl

how to uniquely match each of the words seperated by / in perl ${REP_PATH}/FUNCTIONAL/wide1c_1.0V/max/qor.rpt https://www.unix.com/images/misc/progress.gif (5 Replies)
Discussion started by: dll_fpga
5 Replies

3. Shell Programming and Scripting

reg expression in perl

./GEN_SCR.pl -f ${REP_PATH}/FUNCTIONAL/wide1c_1.0V/max/qor.rpt -o ${REP_PATH}/FUNCTIONAL/GEN2_wide1c_1.0V_max.csv where GEN_SCR.pl is as below...i need to check whether max or min is coming in the argument to the script ...how to do this? ${REP_PATH}/FUNCTIONAL/wide1c_1.0V/max/qor.rpt ... (0 Replies)
Discussion started by: dll_fpga
0 Replies

4. Shell Programming and Scripting

Reg expression

Please let me understand this reg expression (\s+')(.*)('\s+)(.)(.*)(\/.*)/) i have doubt in the below 2.I'm not understanding why back-tick used? (\s+') and ('\s+) (2 Replies)
Discussion started by: dll_fpga
2 Replies

5. UNIX for Dummies Questions & Answers

If Then ElseIf Script - Confusion Around Expression's Syntax

Hello, I am relatively new to UNIX scripting and am learning a lot. I have already tried several searches on this website and have tried various syntax options suggested to no avail. I am obviously not writing the script correctly. I really do appreciate any and all the help. Below is an... (8 Replies)
Discussion started by: dqrgk0
8 Replies

6. Shell Programming and Scripting

awk reg expression

Hello, I have thousand of messages (HL7), I want to use awk to extract only the ones that have a particular value in pv1.18 Each record in the file is the whole HL7 message, ie. when I print $0 I get the whole message MSH EVN PID etc. ,there is an x0d between the segments. I would like to use a... (3 Replies)
Discussion started by: gio001
3 Replies

7. Shell Programming and Scripting

Python (startswith) reg expression

Hello together, Yesterday I have recieved the script in the forum which works well. This script should insert in the previous line, the line that starts with ";". I'd like this process to recur after any arbitrary sign unless there's a number as a sign at the beginning of a line. Actual... (14 Replies)
Discussion started by: research3
14 Replies

8. Shell Programming and Scripting

Reg expression For

HI system.sysUpTime.0 : Timeticks: (1519411311) 175 days, 20:35:13.11 From the above output i need only 175days in a perl script.. Please Help (2 Replies)
Discussion started by: Harikrishna
2 Replies

9. Shell Programming and Scripting

perl reg expression

I have regular expression like this ( replace + with \+) ($mod_server) = ($server =~ /\+/\\+/g); the above is failing with error . what's wrong with it . Thanks (1 Reply)
Discussion started by: talashil
1 Replies

10. UNIX for Dummies Questions & Answers

Help with Reg. Expression

I need help with this: Can any one tell me what does these below mean: 1. "\(.\).*") != '/' 2. sed 's+^\./++;s+/.*++' 3. sed "s+${f}/+ + Thanks in advance (7 Replies)
Discussion started by: moe2266
7 Replies
Login or Register to Ask a Question