This really puzzles me. The following code gives me the error 'expr: syntax error' when I try to do multi-line comment using here document
Even if I explicitly comment out the line containing the expr using "#", the error message would still exist
And I observed that this happens only when I supply the 2nd operand to the expr as variable. If I hardcode it to a numeric value then the error message would disappear, that is
Could anyone enlighten me on this?
Hi,
I came across a script a few months ago that allowed you to use the following script to include the current time into your prompt (useful from auditting purposes):
# Set Prompt
typeset -RZ2 _x1 _x2 _x3
let SECONDS=$(date '+3600*%H+60*%M+%S')... (5 Replies)
I found below script to check whether the variable is a digit in ksh.
############################
#!/bin/ksh
REPLY="3f"
if ]*\)'` != ${REPLY} && "${REPLY}" != "0" ]]
then
print "is digit\n"
else
print "not digit\n"
fi
############################
Although it works fine, but... (6 Replies)
I know I asked a similar question but I want to know if there is a regular expression existing that with a korn shell cmd, finds any timestamp data records in a file where it is greater then a timestamp in a shell variable ?
something like :
grep all records where it has a timestamp >... (5 Replies)
Hi Guys,
THis is the first time am using the expr expression.
I like to know how to write the expression a=(b\100)*a.
THis works fine if it gives without a bracket. the bracket should be present as i wanted to define the order of execution.
Help me out.
Thanks for your help in advance.... (2 Replies)
Is it normal behavior for a shell script that terminates to terminate its parent shell when executed with the "." option?
For example, if I have the example script (we'll name it ex.sh):
#!/bin/sh
if
then
echo "Bye."
exit 2
fi
And I execute it like this:
>./ex.sh
It... (6 Replies)
Hi,
I have line in input file as below:
3G_CENTRAL;INDONESIA_(M)_TELKOMSEL;SPECIAL_WORLD_GRP_7_FA_2_TELKOMSEL
My expected output for line in the file must be :
"1-Radon1-cMOC_deg"|"LDIndex"|"3G_CENTRAL|INDONESIA_(M)_TELKOMSEL"|LAST|"SPECIAL_WORLD_GRP_7_FA_2_TELKOMSEL"
Can someone... (7 Replies)
I've posted about this before, but only recently narrowed the problem down to a specific cause.
Ok, first of all, the behavior:
It occurs when autocompletion brings up its list (not when there is only a single option). Basically, if I were to type, say,
cd ~/<TAB>
I would get something... (2 Replies)
Hi,
I'm trying to sort a text file "test":
S12
S_S12
S_S1_12
S15
S_N15
S_N1_15
By "sort test", I get:
S12
S15
S_N1_15
S_N15
S_S1_12
S_S12
It seems weird:
Comparing Line 2 and Line 3, it must be that '-' is bigger than '1'; however, comparing Line 3 and Line 4, it seems that... (3 Replies)
Hi All,
As per my knowledge in unix, my code looks fine. But still I am getting error (expr:syntax error). Please help me to resolve this error.
Script :
PRE_LBNO=0
PRE_DATE=0
TOT_PAY=0
TOT_REM=0
TOTAL=1
for Record_Type in `cut -c 1 Inputt.dat`
do
if ;
then
CURR_LBNO=` cut -c... (6 Replies)
Hi there,
I'm running into a very weird situation. Let's forget about the purpose of my initial script please. I noticed the bug whatever I'm trying to do.
I'm on an old server running bash 3.1.17.
Say we have the following script :
foo:~# cat /tmp/test
#!/bin/bash
f1() {
local... (9 Replies)
Discussion started by: chebarbudo
9 Replies
LEARN ABOUT BSD
expr
EXPR(1) General Commands Manual EXPR(1)NAME
expr - evaluate arguments as an expression
SYNOPSIS
expr arg ...
DESCRIPTION
The arguments are taken as an expression. After evaluation, the result is written on the standard output. Each token of the expression is
a separate argument.
The operators and keywords are listed below. The list is in order of increasing precedence, with equal precedence operators grouped.
expr | expr
yields the first expr if it is neither null nor `0', otherwise yields the second expr.
expr & expr
yields the first expr if neither expr is null or `0', otherwise yields `0'.
expr relop expr
where relop is one of < <= = != >= >, yields `1' if the indicated comparison is true, `0' if false. The comparison is numeric if
both expr are integers, otherwise lexicographic.
expr + expr
expr - expr
addition or subtraction of the arguments.
expr * expr
expr / expr
expr % expr
multiplication, division, or remainder of the arguments.
expr : expr
The matching operator compares the string first argument with the regular expression second argument; regular expression syntax is
the same as that of ed(1). The (...) pattern symbols can be used to select a portion of the first argument. Otherwise, the
matching operator yields the number of characters matched (`0' on failure).
( expr )
parentheses for grouping.
Examples:
To add 1 to the Shell variable a:
a=`expr $a + 1`
To find the filename part (least significant part) of the pathname stored in variable a, which may or may not contain `/':
expr $a : '.*/(.*)' '|' $a
Note the quoted Shell metacharacters.
SEE ALSO sh(1), test(1)DIAGNOSTICS
Expr returns the following exit codes:
0 if the expression is neither null nor `0',
1 if the expression is null or `0',
2 for invalid expressions.
7th Edition April 29, 1985 EXPR(1)