Use quotes around it, so you can avoid variable expansion in shell.
What is that, pamu?
Variable expansion will be done by the shell in any case (in case of double-quotes). The double-quotes are to retain the embedded spaces and/or to tell the shell that the parameter exists (in case of null strings) in case of [..] construct.
You don't require the quotes in case [[..]] construct (unless you are testing strings as is).
Also, in the [[..]], globbing is not done.
In ksh88,
Last edited by elixir_sinari; 10-01-2012 at 08:38 AM..
This User Gave Thanks to elixir_sinari For This Post:
hi, unix gurus.
i am wondering if someone can give me a clear explanation of the differneces between parentheses and brackets, both single and double.
i have heard that double parentheses (( are used for numerical expressions and that single brackets [ are used for strings. but i see... (1 Reply)
One of the senior administrators gave me a shell script to modify and it begins as follows:
if ] && ]
{more code follows}
Why the double square brackets? (10 Replies)
Hi
First apologies if this has been raised before.
I've got the following in a ksh script:
if ]
For some reason this does not work. But if I remove the double square brackets to:
if
This works.
I thought ksh supported the ]. Or is there more to it?
Thanks in advance. (3 Replies)
Hi,
I just came across an interesting shell script syntax like the one below:
] && (trap 'rm -rf ${WORK_DIR}/*.$$; echo "\n\nInterrupted !!\n\n"; exit 4' 1 2 3 15)
Can someone please explain the code snippet above?
The trap command bit is fine but ] && is the hazy part.
Generally we use an... (2 Replies)
Hi All,
I have a text file which looks like this:
computer programming
systems engineering
I want to get rid of these square brackets and also the text that is inside these brackets. So that my final text file looks like this:
computer programming
systems engineering
I am using... (3 Replies)
I wanted to compare the value inside the Squre bracket after Colon ( : ) based on any value(seperated by or operator | ) inside the variable Thread and if match found then wnated to store in output file
Input file :
20140320 00:08:43.918 INO 35] - Corporate hub is
20140320 00:08:43.918... (2 Replies)
I wanted to store the number inside the square bracket between colon( : ) and closing suqre bracket(]) in some variable.
Suppose I have lines like :
Input file :
20140320 00:08:23.846 INFO 84] - anything in line
20140320 00:08:23.846 Test 589] - Virtual and lab lab anything... (18 Replies)
Hi All,
Hope you all are doing good. Yesterday in my project i came across a scenario which i can not guess why it was working in one region and why it was not in another region. Please find my issue below.
I am using AIX version 6.0 of UNIX in my project, in shell scripting i have the... (1 Reply)
Discussion started by: mad man
1 Replies
LEARN ABOUT FREEBSD
cbrtl
SQRT(3) BSD Library Functions Manual SQRT(3)NAME
cbrt, cbrtf, cbrtl, sqrt, sqrtf, sqrtl -- cube root and square root functions
LIBRARY
Math Library (libm, -lm)
SYNOPSIS
#include <math.h>
double
cbrt(double x);
float
cbrtf(float x);
long double
cbrtl(long double x);
double
sqrt(double x);
float
sqrtf(float x);
long double
sqrtl(long double x);
DESCRIPTION
The cbrt(), cbrtf(), and cbrtl() functions compute the cube root of x.
The sqrt(), sqrtf(), and sqrtl() functions compute the non-negative square root of x.
RETURN VALUES
The cbrt(), cbrtf(), and cbrtl() functions return the requested cube root. The sqrt(), sqrtf(), and sqrtl() functions return the requested
square root unless an error occurs. An attempt to take the sqrt() of negative x raises an invalid exception and causes an NaN to be returned
(except that the square root of -0 is valid and equal to -0.)
SEE ALSO fenv(3), math(3)STANDARDS
The cbrt(), cbrtf(), cbrtl(), sqrt(), sqrtf(), and sqrtl() functions conform to ISO/IEC 9899:1999 (``ISO C99'').
HISTORY
The cbrt() function appeared in 4.3BSD. The sqrtl() function appeared in FreeBSD 8.0. The cbrtl() function appeared in FreeBSD 9.0.
BSD March 5, 2011 BSD