Hi
I am trying to write a function that needs to be able to assign the last run shell command to a variable. The actual command string itself not the exit code of the command.
I am using the bash command recall ability to do this as follows:
alias pb='ps | grep ash' ... (3 Replies)
Hi Friends...
Please assist me to assign the result of a SQL query that results two column, to two variables.
Pls find the below code that I write for assigning one column to one variable. and please correct if anything wrong..
#! /bin/sh
no='
sqlplus -s uname/password@DBname... (4 Replies)
Hi ,
I would like to assign command (with pipe) output to a variable. The code is as follows. The goal of the code is to get the last folder folder with a particular name pattern.
myDate=`ls | grep 2009 | tail -1`
echo "myDate=" $myDate
However, in the presence of the pipe, the code... (3 Replies)
Code
set -x
STATUS="0"
echo $STATUS
for i in `ls -ltr Report*|awk '{ print $9 }'`
do
if
then
flg = "`head -1 "$i" |cut -c 31-33`"
echo `head -1 "$i" |cut -c 31-33`
echo $flg
if
then
echo "having Fun"
STATUS="2"
else
echo "no Fun"
fi
fi (2 Replies)
Hi,
I have the following command that lists all the .o files from all the directories except of vwin (which I don't want it)
for i in `ls -d */*.o|awk '$0 !~ "vwin"'`; do echo $i; done
The result is something like that
dir1/file1.o
dir1/file2.o
dir2/file3.o
etc.
So, I want to create a... (9 Replies)
Hey guys. Below is the command I am using to assign "yellow" to the variable yellow. I can seem to echo it out using xargs but when I assign it to yellow and then try to echo it out it prints a blank line.
Below is the command. Your help is highly appreciated!
cut -c 2- color.txt |... (11 Replies)
Hello All,
Hope you're doing well !
I am trying below command to be passed in a shell script, header_date_14 is a variable and $1 is the name of a file I intend to pass as a command line argument, however command line argument is not being accepted.
header_date_14=$(m_dump... (8 Replies)
In the else of the main if condition .
else
set lnk = $(readlink -f <path> | cut -d '/' -f7)
echo "$lnk"
if ]
When I run the above on command line , the execution seems to be fine and I get the desired output. But when I try to assign it to a variable within a loop... (12 Replies)
Hi,
I have the script below. When i assign SSH_COMMAND to "ssh -o ConnectTimeout=2 ${SERVER} ${AS_SUDO} ${COMMANDS}" and then execute it as ${SSH_COMMAND} I get the following error:
ssh: Could not resolve hostname sudo: Name or service not known
ssh: Could not resolve hostname sudo: Name or... (3 Replies)
Discussion started by: mohca2020
3 Replies
LEARN ABOUT LINUX
expr
EXPR(1) User Commands EXPR(1)NAME
expr - evaluate expressions
SYNOPSIS
expr EXPRESSION
expr OPTION
DESCRIPTION --help display this help and exit
--version
output version information and exit
Print the value of EXPRESSION to standard output. A blank line below separates increasing precedence groups. EXPRESSION may be:
ARG1 | ARG2
ARG1 if it is neither null nor 0, otherwise ARG2
ARG1 & ARG2
ARG1 if neither argument is null or 0, otherwise 0
ARG1 < ARG2
ARG1 is less than ARG2
ARG1 <= ARG2
ARG1 is less than or equal to ARG2
ARG1 = ARG2
ARG1 is equal to ARG2
ARG1 != ARG2
ARG1 is unequal to ARG2
ARG1 >= ARG2
ARG1 is greater than or equal to ARG2
ARG1 > ARG2
ARG1 is greater than ARG2
ARG1 + ARG2
arithmetic sum of ARG1 and ARG2
ARG1 - ARG2
arithmetic difference of ARG1 and ARG2
ARG1 * ARG2
arithmetic product of ARG1 and ARG2
ARG1 / ARG2
arithmetic quotient of ARG1 divided by ARG2
ARG1 % ARG2
arithmetic remainder of ARG1 divided by ARG2
STRING : REGEXP
anchored pattern match of REGEXP in STRING
match STRING REGEXP
same as STRING : REGEXP
substr STRING POS LENGTH
substring of STRING, POS counted from 1
index STRING CHARS
index in STRING where any CHARS is found, or 0
length STRING
length of STRING
+ TOKEN
interpret TOKEN as a string, even if it is a
keyword like `match' or an operator like `/'
( EXPRESSION )
value of EXPRESSION
Beware that many operators need to be escaped or quoted for shells. Comparisons are arithmetic if both ARGs are numbers, else lexicograph-
ical. Pattern matches return the string matched between ( and ) or null; if ( and ) are not used, they return the number of characters
matched or 0.
Exit status is 0 if EXPRESSION is neither null nor 0, 1 if EXPRESSION is null or 0, 2 if EXPRESSION is syntactically invalid, and 3 if an
error occurred.
AUTHOR
Written by Mike Parker, James Youngman, and Paul Eggert.
REPORTING BUGS
Report expr bugs to bug-coreutils@gnu.org
GNU coreutils home page: <http://www.gnu.org/software/coreutils/>
General help using GNU software: <http://www.gnu.org/gethelp/>
Report expr translation bugs to <http://translationproject.org/team/>
COPYRIGHT
Copyright (C) 2010 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html>.
This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law.
SEE ALSO
The full documentation for expr is maintained as a Texinfo manual. If the info and expr programs are properly installed at your site, the
command
info coreutils 'expr invocation'
should give you access to the complete manual.
GNU coreutils 8.5 February 2011 EXPR(1)