10 More Discussions You Might Find Interesting
1. Shell Programming and Scripting
HI there
I am trying to understand Shell scripting to create my own, I am attempting a few examples can anyone tell me what this means?n=$( expr $n + 1)Tried looking on the internet, but just cannot find its anywhere :( .Help please (4 Replies)
Discussion started by: steve2015
4 Replies
2. Shell Programming and Scripting
Hi
I have bellow script:
t1=`cat node1.txt | grep thread1 | cut -f2 -d '-'`
t2=`cat node2.txt | grep thread2 | cut -f2 -d '-'`
t3=`cat node1_rcat.txt | grep thread1 | cut -f2 -d '-'`
t4=`cat node2_rcat.txt | grep thread2 | cut -f2 -d '-'`
if ]; then
echo "no restore" >> log.log... (6 Replies)
Discussion started by: primo102
6 Replies
3. Shell Programming and Scripting
Hi All,
I'm writing a shell script in KSH, where I want to store the filename, total record count and actual record count of all the source files. The source files reside in 4 different sub-folders under the same root folder.
Below is code:
#!/usr/bin/ksh... (6 Replies)
Discussion started by: jagari
6 Replies
4. UNIX for Dummies Questions & Answers
i have been told that 'let' is faster than 'expr' in terms of performance.
Is this correct? if yes, why is it so?
i am not able to see any performance difference in small arithmetic operations.
Thanks (3 Replies)
Discussion started by: pandeesh
3 Replies
5. UNIX for Dummies Questions & Answers
Hey there
i want to subtract the content from $b from $a. Each variable has got 18 values (normal numbers from 0 - 99).
How can i subtract them? I know i have to use the expr command, this is what i have till now:
a=`cat Tabelle.dat | awk {'print $4'} | awk -F: {'print $1'}`
b=`cat... (1 Reply)
Discussion started by: Mad van Bert
1 Replies
6. Shell Programming and Scripting
$ cat > mtable
#!/bin/sh
#
#Script to test for loop
#
#
if
then
echo "Error - Number missing form command line argument"
echo "Syntax : $0 number"
echo "Use to print multiplication table for given number"
exit 1
fi
n=$1
for i in 1 2 3 4 5 6 7 8 9 10
do
echo "$n * $i = `expr $i \*... (1 Reply)
Discussion started by: jackel7777
1 Replies
7. Shell Programming and Scripting
What is the difference between test expr VS .
For example :
if test 5 -eq 6
echo "Wrong"
and
if
echo "Wrong"
bot will give the same output as Wrong.
Now, what is the difference between these two? though they are producing the same result why we need two?
Any answer will be... (2 Replies)
Discussion started by: ashok.g
2 Replies
8. Red Hat
i am new to shell programming, currently using redhat linux of version
2.4.20-8.
i have problem in executing expr command in the following shell script
$ x=5
$ x='expr $x + 1'
$ echo $x
the output is displaying always
expr $x + 1
Pls guide me for the above query (3 Replies)
Discussion started by: saikumarm80
3 Replies
9. UNIX for Dummies Questions & Answers
I am running the following
Y=05
Y=`expr $X - 1`
and I getting a result of 4. Does anyone know if there is a way to make the result 04 instead of 4? (3 Replies)
Discussion started by: low90s
3 Replies
10. UNIX for Dummies Questions & Answers
Hello!
I want to evaluate some mathematical expressions in a script and I try to use 'expr' command.
Unfortunatally, when I have, for example,
expr 8.2 + 6
the result is 'expr: non-numeric argument'
Why ?
I work on SunOs 5.7.
Thanks in advance
Nathe (5 Replies)
Discussion started by: Nathe
5 Replies
test(1) General Commands Manual test(1)
Name
test - test conditional expression
Syntax
test expr
[ expr ]
Description
The command evaluates the expression expr. If the value of expr is true, the command returns a zero exit status; otherwise, it returns a
nonzero exit status. The command also returns a nonzero exit status if no arguments are specified.
Options
The following primitives are used to construct expr:
-r file Tests if the file exists and is readable.
-w file Tests if the file exists and is writable.
-f file Tests if the file exists and is not a directory.
-d file Tests if the file exists and is a directory.
-s file Tests if the file exists and has a size greater than zero.
-t [ fildes ] Tests if the open file, whose file descriptor number is fildes (1 by default), is associated with a terminal device.
-z s1 Tests if the length of string s1 is zero.
-n s1 Tests if the length of the string s1 is nonzero.
s1 = s2 Tests if the strings s1 and s2 are equal.
s1 != s2 Tests if the strings s1 and s2 are not equal.
s1 Tests if s1 is not the null string.
n1 -eq n2 Tests if number1 equals number2.
n1 -ge n2 Tests if number1 is greater than or equal to number2.
n1 -gt n2 Tests if number1 is greater than number2.
n1 -le n2 Tests if number1 is less than or equal to number2.
n1 -lt n2 Tests if number1 is less than number2.
n1 -ne n2 Tests if number1 is not equal to number2.
These primitives can be combined with the following operators:
!expr Negates evaluation of expression.
expr -a expr Tests logical and of two expressions.
expr -o expr Tests logical or of two expressions.
( expr... ) Groups expressions.
The -a operator takes precedence over the -o operator. Note that all the operators and flags are separate arguments to Note also that
parentheses are meaningful to the Shell and must be escaped.
See Also
find(1), sh(1), test(1sh5)
test(1)
