Using grep with test and without using [[ ]] Post: 303029212

Sponsored Content

Top Forums Shell Programming and Scripting Using grep with test and without using [[ ]] Post 303029212 by wisecracker on Wednesday 23rd of January 2019 07:26:44 AM

01-23-2019

Registered User

Hi MadeInGermany...
(Or anyone...)

Relative to this thread as you have used 'case....esac':
What is the reasoning behind ;;, why 2 semicolons instead of 1, after each command inside a 'case' statement?
I have always wondered as I can't find any mention of it.
A question to help our newbie friend to understand too.

Code:

Last login: Wed Jan 23 12:04:15 on ttys000
AMIGA:amiga~> help case
case: case WORD in [PATTERN [| PATTERN]...) COMMANDS ;;]... esac
    Selectively execute COMMANDS based upon WORD matching PATTERN.  The
    `|' is used to separate multiple patterns.
AMIGA:amiga~> _

And from the manual, (man bash):

Code:

       case word in [ [(] pattern [ | pattern ] ... ) list ;; ] ... esac
              A case command first expands word, and tries to match it against
              each pattern in turn, using the same matching rules as for path-
              name expansion (see Pathname  Expansion  below).   The  word  is
              expanded  using  tilde  expansion, parameter and variable expan-
              sion, arithmetic  substitution,  command  substitution,  process
              substitution  and  quote  removal.   Each  pattern  examined  is
              expanded using tilde expansion, parameter  and  variable  expan-
              sion, arithmetic substitution, command substitution, and process
              substitution.  If the shell option nocasematch is  enabled,  the
              match  is  performed  without  regard  to the case of alphabetic
              characters.  When a match is found, the  corresponding  list  is
              executed.   After  the  first  match,  no subsequent matches are
              attempted.  The exit status is zero if no pattern matches.  Oth-
              erwise,  it  is  the exit status of the last command executed in
              list.

This User Gave Thanks to wisecracker For This Post:

wisecracker

View Public Profile for wisecracker

Find all posts by wisecracker

10 More Discussions You Might Find Interesting

1. Shell Programming and Scripting

Using grep in a test/if statement

Okay, well this is more or less my first attempt at writing a shell script. Anyways, here's my code: cd ${PATH} if then rm ${FILE} ./anotherScript else exit 1 fi exit 1 Anyways, it's a pretty simple script that is supposed to search for the...

2. UNIX for Dummies Questions & Answers

Unix grep/test command

Hello, i have a script which checks if the user entered 8 numeric characters in the form of YYYYMMDD (birth date). If the user entered any non numeric characters, an error will be displayed: # Check to see if the 8 characters are all numbers # If not show error essage # And prompt user...

3. Shell Programming and Scripting

Using grep inside a test

Hi, I want to use grep inside a test statement, but I am getting an error message. Two variables testvarNum=5 testvarNonNum=x echo $testvarNum | grep * The result of this is as follows: 5 However, when I try the following (i.e. to test if the variable is numeric or non-numeric):...

4. Shell Programming and Scripting

Test on string containing spacewhile test 1 -eq 1 do read a $a if test $a = quitC then break fi d

This is the code: while test 1 -eq 1 do read a $a if test $a = stop then break fi done I read a command on every loop an execute it. I check if the string equals the word stop to end the loop,but it say that I gave too many arguments to test. For example echo hello. Now the...

5. Shell Programming and Scripting

grep functions, how to test if succeeded

Hello ...again. I am stuck on this part, I have a loop with processes an operations file. and calls different functions depending on what is in loop, which processes a database file... #so far my add function works as intended add() { ...blah blah; } # delete is kinda working...

6. Shell Programming and Scripting

How to check weather a string is like test* or test* ot test in if condition

How to check weather a string is like test* or test* ot *test* in if condition

7. Shell Programming and Scripting

searching fileextentions (suffix) with grep and/or test

Hello, I have a problem. I will search files on fileextentions (suffix). It can with the command find, but I will do it with the commands grep and/or test. When i start the script I will see all files with that extention (suffix). Can anyone help me, please? Thanks! Regards, Arjan...

8. Shell Programming and Scripting

If test grep.... always returns 0 status

Hi all. I am trying to compare and filter two files. I have a bigfile.txt of names and ids and a smallfile.txt of ids only. What I am trying to do is use a while read loop to read the ids in the bigfile and then echo the name and id only if the id exists in the small file. Basically, I'm trying to...

9. Shell Programming and Scripting

Grep/print/ a test file

cat abc.txt Filename: SHA_AED_Monthly_SNR_20150331.txt.gz Data Format: ASCII with carriage returns and linefeeds Compression: GZIP GZIP Bytes: 36893068 Unzipped Bytes : 613794510 Records: 851310 Record Length: 738 Blocksize: 32472 Filename: SHA_AED_SNR_ChangeLog_20150331.txt.gz Data...

10. UNIX for Beginners Questions & Answers

Is it correct? if test grep EOF $a ...

read a if test grep EOF $a then echo yes file else echo no fi

LEARN ABOUT OPENDARWIN

tcl_stringcasematch

Tcl_StringMatch(3)					      Tcl Library Procedures						Tcl_StringMatch(3)

__________________________________________________________________________________________________________________________________________________

NAME

       Tcl_StringMatch, Tcl_StringCaseMatch - test whether a string matches a pattern

SYNOPSIS

       #include <tcl.h>

       int
       Tcl_StringMatch(string, pattern)

       int
       Tcl_StringCaseMatch(string, pattern, nocase)

ARGUMENTS

       char	    *string	       (in)	 String to test.

       char	    *pattern	       (in)	 Pattern to match against string.  May contain special characters from the set *?[].

       int	    nocase	       (in)	 Specifies whether the match should be done case-sensitive (0) or case-insensitive (1).
_________________________________________________________________

DESCRIPTION

       This  utility  procedure  determines  whether  a  string  matches  a given pattern.  If it does, then Tcl_StringMatch returns 1.  Otherwise
       Tcl_StringMatch returns 0.  The algorithm used for matching is the same algorithm used in the ``string match'' Tcl command and  is  similar
       to the algorithm used by the C-shell for file name matching;  see the Tcl manual entry for details.					   |

       In  Tcl_StringCaseMatch,  the algorithm is the same, but you have the option to make the matching case-insensitive.  If you choose this (by |
       passing nocase as 1), then the string and pattern are essentially matched in the lower case.

KEYWORDS

       match, pattern, string

Tcl									8.1							Tcl_StringMatch(3)

10 More Discussions You Might Find Interesting

1. Shell Programming and Scripting

Using grep in a test/if statement

Discussion started by: cbo0485

2. UNIX for Dummies Questions & Answers

Unix grep/test command

Discussion started by: netmaster

3. Shell Programming and Scripting

Using grep inside a test

Discussion started by: dkieran

4. Shell Programming and Scripting

Test on string containing spacewhile test 1 -eq 1 do read a $a if test $a = quitC then break fi d

Discussion started by: Max89