I am looking for the correct syntax on the expr command in UNIX. I have a script that I am building at the moment. the script is creating file1 that is an actual .sql file that is going inside the oracle database to get some information in there. It take that information, puts it inside another... (2 Replies)
Hi All,
I might be making a silly mistake but I need ur help.
I have initialized various variables:
cur_month=`date +%m`
cur_year=`date +%y`
last_year=`expr $cur_year \- 1`
It works fine for cur_month & cur_year....but has problems with last_year.
FOR LAST YEAR IT GIVES A FOLLOWING... (2 Replies)
Hi All,
I have created 85 users on Linux server.
I use bsh shell for all users.But after any user get logged in on unix,he/she is not able to access the expr command.So anyone can tell me that if i have to include some files to access expr command.Because when i write-> expr 6+2 on $ prompt i'll... (1 Reply)
hi guys....
i hava a command expr... where i m adding a value in a loop
like
Tc=`expr $Tc\+ $l`
where
Tc is declred as a variable and every time l contains a new vaue
if
Tc =0 initially
and l =2
Tc should be equal to 0+ 2
and then
l = 4
Tc = 2+4
and dispaly as 6
but after... (5 Replies)
:)
hi Unix gurus,
Pls consider the following piece of code
str='hello'
length=echo $str|wc -c
echo $length
y= ` expr \( 80 - $length \) `
echo $y
:confused:
The last echo stmt is displaying 0 as the result.
If i put direct value like 6 instead of $length in i 3rd stmt it is giving... (8 Replies)
Hi
Can anyone explain me the usage of this command and the arguments used here and what will be the expected output :
v_num=`expr nav_d_20100204_1759 : '*\(*\)'`
what will be the value returned in v_num.
Thanks in Advance!!!
Regards
Naveen Purbia (3 Replies)
Hi,
I am trying to code a unix function to calculate date difference between two date variables. I am stuck at a point where I am trying to convert hours into minutes. Below is the code I am doing.
function get_elapsed_time
{
export PROPS_FILE=temp.properties
export... (8 Replies)
I'm trying to check if a variable'd string is only one character and use that in an if statement the only way I could find is:
$expr "${var}" : . # expr STRING : regrep
where the "." is the grep wildcard for any single character.
Whats wrong with my code here and is there a... (3 Replies)
Discussion started by: Tewg
3 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)