06-28-2013
Single quotes turn of meta meanings entirely, so I prefer them, generally. When setting PS1:
- anything for evaluation later must be in single quotes, like $PWD or an effective id or date call.
- Things you can set at login time, like login id, tty or host name, can be barefoot or in double quotes.
This User Gave Thanks to DGPickett For This Post:
10 More Discussions You Might Find Interesting
1. UNIX for Dummies Questions & Answers
Hello, I'm trying to use grep or egrep to exclude a whole range of characters but how do I exclude both a single and a double quote.
It might be easier to say how do I use grep to find both single and double quotes.
grep ' ' " ' file
grep detects the first single quote within my... (4 Replies)
Discussion started by: Lindy_so
4 Replies
2. Shell Programming and Scripting
I'm not very familiar with the ssh command. When I tried to set a variable and then echo its value on a remote machine via ssh, I found a problem. For example,
$ ITSME=itsme
$ ssh xxx.xxxx.xxx.xxx "ITSME=itsyou; echo $ITSME"
itsme
$ ssh xxx.xxxx.xxx.xxx 'ITSME=itsyou; echo $ITSME'
itsyou
$... (3 Replies)
Discussion started by: password636
3 Replies
3. Shell Programming and Scripting
Hi,
I am trying to write the following command as an alias in my .bashrc file.
bjobs -u all | awk '{if (NR > 1) {username++;}}END{{print"\nJOBS BY USER:\n"} for (i in username) {print username,i;}{print"\n Total Jobs=",NR-1,"\n" }}'
The command simply puts how many jobs each user is... (2 Replies)
Discussion started by: jacekmaciek
2 Replies
4. Shell Programming and Scripting
Hi guys, I have a sed line in double quotes which works fine, but I want it to be in single quotes
here is the sed line
sed "/abc_def/s/\'.*\'/\'\${abc_def}\'/"
can some one give the equivalent to the above script in single quotes
Thanks a ton (5 Replies)
Discussion started by: sol_nov
5 Replies
5. UNIX for Dummies Questions & Answers
Unix superusers,
I am new to unix but would like to learn more about grep. I am very familiar with regular expressions as i have used them for searching text files in windows based text editors. Since I am not very familiar with Unix, I dont understand when one should use GREP with the... (2 Replies)
Discussion started by: george_vandelet
2 Replies
6. UNIX for Dummies Questions & Answers
Hi Unix experts,
Believe me, this forum has been really great help and I searched for many things that were already answered before open new post that were just new versions of old one, but with this one, I just can't simply move any forward.
This must be quite easy, but I cant find where I... (1 Reply)
Discussion started by: manolain
1 Replies
7. Shell Programming and Scripting
Hello. I'm trying to write a bash script that uses GNU screen and have hit a brick wall that has cost me many hours... (I'm sure it has something to do with quoting/globbing, which is why I post it here)
I can make a script that does the following just fine:
test.sh:
#!/bin/bash
# make... (2 Replies)
Discussion started by: jondecker76
2 Replies
8. UNIX for Dummies Questions & Answers
Hi i have to insert the below line into a specific line number of another file
export MBR_CNT_PRCP_TYPE_CODES_DEL="'01','02','04','05','49','55','UNK'"
I have passed the above line to a variable say ins_line. I have used below command to perform the insert
awk 'NR==3{print "'"${ins_line}"'"}1'... (1 Reply)
Discussion started by: sathishteradata
1 Replies
9. Shell Programming and Scripting
Hi Froum.
I have tried in vain to find a solution for this problem - I'm trying to replace any double quotes within a quoted string with a single quote, leaving everything else as is.
I have the following data:
Before:
... (32 Replies)
Discussion started by: pchang
32 Replies
10. Shell Programming and Scripting
Hi All,
I'm unable to load the data using sql loader where there are double quotes within the double quotes As these are optionally enclosed by double quotes.
Sample Data :
"221100",138.00,"D","0019/1477","44012075","49938","49938/15043000","Television - 22" Refurbished - Airwave","Supply... (6 Replies)
Discussion started by: mlavanya
6 Replies
LEARN ABOUT CENTOS
perl::critic::policy::valuesandexpressions::prohibitinterpolatio
Perl::Critic::Policy::ValuesAndExpressions::ProhibitInteUseraContribPerl::Critic::Policy::ValuesAndExpressions::ProhibitInterpolationOfLiterals(3)
NAME
Perl::Critic::Policy::ValuesAndExpressions::ProhibitInterpolationOfLiterals - Always use single quotes for literal strings.
AFFILIATION
This Policy is part of the core Perl::Critic distribution.
DESCRIPTION
Don't use double-quotes or "qq//" if your string doesn't require interpolation. This saves the interpreter a bit of work and it lets the
reader know that you really did intend the string to be literal.
print "foobar"; #not ok
print 'foobar'; #ok
print qq/foobar/; #not ok
print q/foobar/; #ok
print "$foobar"; #ok
print "foobar
"; #ok
print qq/$foobar/; #ok
print qq/foobar
/; #ok
print qq{$foobar}; #preferred
print qq{foobar
}; #preferred
Use of double-quotes might be reasonable if the string contains single quote (') characters:
print "it's me"; # ok, if configuration flag set
CONFIGURATION
The types of quoting styles to exempt from this policy can be configured via the "allow" option. This must be a whitespace-delimited
combination of some or all of the following styles: "qq{}", "qq()", "qq[]", and "qq//".
This is useful because some folks have configured their editor to apply special syntax highlighting within certain styles of quotes. For
example, you can tweak "vim" to use SQL highlighting for everything that appears within "qq{}" or "qq[]" quotes. But if those strings are
literal, Perl::Critic will complain. To prevent this, put the following in your .perlcriticrc file:
[ValuesAndExpressions::ProhibitInterpolationOfLiterals]
allow = qq{} qq[]
The flag "allow_if_string_contains_single_quote" permits double-quoted strings if the string contains a single quote (') character. It
defaults to off; to turn it on put the following in your .perlcriticrc file:
[ValuesAndExpressions::ProhibitInterpolationOfLiterals]
allow_if_string_contains_single_quote = 1
SEE ALSO
Perl::Critic::Policy::ValuesAndExpressions::RequireInterpolationOfMetachars
AUTHOR
Jeffrey Ryan Thalhammer <jeff@imaginative-software.com>
COPYRIGHT
Copyright (c) 2005-2011 Imaginative Software Systems. All rights reserved.
This program is free software; you can redistribute it and/or modify it under the same terms as Perl itself. The full text of this license
can be found in the LICENSE file included with this module.
perl v5.16.3 Perl::Critic::Policy::ValuesAndExpressions::ProhibitInterpolationOfLiterals(3)