02-02-2019
Please post (at least) OS and shell versions in every new thread that you create, so to avoid ambiguities and keep people from guessing. In above case, also the language / compiler that the construct is used for / with.
Last edited by RudiC; 02-02-2019 at 08:22 AM..
10 More Discussions You Might Find Interesting
1. Shell Programming and Scripting
i have following if condition
if
above statement is case sensitive.....what is syntax if i have to make above comparision case insensetive (4 Replies)
Discussion started by: mahabunta
4 Replies
2. Shell Programming and Scripting
Hi friends, :)
In a shell script i found the following if condition.
echo -n "Which version of $1 do you want to restore ('0' to quit)? : "
read desired
if ${desired:=1} -ge $index ] ; then
echo "$0: Restore canceled by user: index value too big." >&2
exit 1
fi
Can... (1 Reply)
Discussion started by: ravi raj kumar
1 Replies
3. Shell Programming and Scripting
i have a paramter data_date in which i am passing a string value.i want to find out another paramter file_date from this.the logic is given below
if day of data_date = sunday or monday
then
file_date=data_date-1
else
file_date=data_date-2
i am passing data_date as 20061027.
how can i... (3 Replies)
Discussion started by: dr46014
3 Replies
4. Shell Programming and Scripting
Hi,
I am trying to execute this command, but is it not working, says "`;' unexpected"
eval $lgrep $SAM_CMD ; if ; then ; echo "No Error" ; fi
What i want is, return the command output, if it is non zero, say "No Error".
Thanks, John. (21 Replies)
Discussion started by: john_prince
21 Replies
5. HP-UX
Executed the following if conditions .. and got different results .
only (( )) gave correct o/p with all scenarios .
Can anybody please let me know what is the difference between and ] and ((condition)) when used with if condition.
And why each condition gave different result.
1.... (2 Replies)
Discussion started by: soumyabubun
2 Replies
6. Shell Programming and Scripting
hi,
I have some problems in my simple script about the redirect echo stdout command inside a condition. Why is the echo command inside the elif still execute in the else command
Here are my simple script
After check on the two diff output the echo stdout redirect is present in two diff... (3 Replies)
Discussion started by: jao_madn
3 Replies
7. Shell Programming and Scripting
if
chr1:109457160 1 109457160 99.1735537190083 +
chr1:109457233 1 109457233 99.1735537190083 -
chr1:109457614 1 109457614 99.1735537190083 +
chr1:109457618 1 109457618 100 +
chr1:109457943 1 109457943 100 -
chr1:109458224 1 109458224 99.1735537190083 -
file1.txt
If 6th column in... (3 Replies)
Discussion started by: johnkim0806
3 Replies
8. Shell Programming and Scripting
HI
My doubt may be basic one but I need to get it clarified..
When i use "if" condition that checks for many AND, OR logical conditions
like
if ]; then
return 0
fi
Even the if condition fails it returns as zero.. Any clue..
But if i add else condition like
if ]; ... (2 Replies)
Discussion started by: Priya Amaresh
2 Replies
9. UNIX for Dummies Questions & Answers
Hi all
Unix newbie - please be gentle
Am modifying an existing script to error trap a variable with a length of 0
#!/bin/bash
ipfile='/var/data/bin/ipaddress'
] && ipold="$(< "$ipfile" )"
ipnew="$( wget -q -O - checkip.dyndns.org | sed -e 's/.*Current IP Address: //;s/<.*$//' )"
#... (6 Replies)
Discussion started by: CRChamberlain
6 Replies
10. Shell Programming and Scripting
o/p of my command is given below
My requirement is
if Pnumber is 0 then
stabilization.Build.2013
else
stabilization.PBuild.2013.3 (11 Replies)
Discussion started by: nikhil jain
11 Replies
LEARN ABOUT OSX
feature5.12
feature(3pm) Perl Programmers Reference Guide feature(3pm)
NAME
feature - Perl pragma to enable new features
SYNOPSIS
use feature qw(switch say);
given ($foo) {
when(1) { say "$foo == 1" }
when ([2,3]) { say "$foo == 2 || $foo == 3" }
when (/^a[bc]d$/) { say "$foo eq 'abd' || $foo eq 'acd'" }
when ($_ > 100) { say "$foo > 100" }
default { say "None of the above" }
}
use feature ':5.10'; # loads all features available in perl 5.10
DESCRIPTION
It is usually impossible to add new syntax to Perl without breaking some existing programs. This pragma provides a way to minimize that
risk. New syntactic constructs, or new semantic meanings to older constructs, can be enabled by "use feature 'foo'", and will be parsed
only when the appropriate feature pragma is in scope.
Lexical effect
Like other pragmas ("use strict", for example), features have a lexical effect. "use feature qw(foo)" will only make the feature "foo"
available from that point to the end of the enclosing block.
{
use feature 'say';
say "say is available here";
}
print "But not here.
";
"no feature"
Features can also be turned off by using "no feature "foo"". This too has lexical effect.
use feature 'say';
say "say is available here";
{
no feature 'say';
print "But not here.
";
}
say "Yet it is here.";
"no feature" with no features specified will turn off all features.
The 'switch' feature
"use feature 'switch'" tells the compiler to enable the Perl 6 given/when construct.
See "Switch statements" in perlsyn for details.
The 'say' feature
"use feature 'say'" tells the compiler to enable the Perl 6 "say" function.
See "say" in perlfunc for details.
the 'state' feature
"use feature 'state'" tells the compiler to enable "state" variables.
See "Persistent Private Variables" in perlsub for details.
the 'unicode_strings' feature
"use feature 'unicode_strings'" tells the compiler to treat all strings outside of "use locale" and "use bytes" as Unicode. It is available
starting with Perl 5.11.3.
See "The "Unicode Bug"" in perlunicode for details.
FEATURE BUNDLES
It's possible to load a whole slew of features in one go, using a feature bundle. The name of a feature bundle is prefixed with a colon, to
distinguish it from an actual feature. At present, the only feature bundle is "use feature ":5.10"" which is equivalent to "use feature
qw(switch say state)".
Specifying sub-versions such as the 0 in 5.10.0 in feature bundles has no effect: feature bundles are guaranteed to be the same for all
sub-versions.
IMPLICIT LOADING
There are two ways to load the "feature" pragma implicitly :
o By using the "-E" switch on the command-line instead of "-e". It enables all available features in the main compilation unit (that is,
the one-liner.)
o By requiring explicitly a minimal Perl version number for your program, with the "use VERSION" construct, and when the version is
higher than or equal to 5.10.0. That is,
use 5.10.0;
will do an implicit
use feature ':5.10';
and so on. Note how the trailing sub-version is automatically stripped from the version.
But to avoid portability warnings (see "use" in perlfunc), you may prefer:
use 5.010;
with the same effect.
perl v5.12.5 2012-11-03 feature(3pm)