Logic of code
if ( $var is a number ) {
Do something
}
else {
Do something else
}
My question is: How do I check if a variable is a number. All the reg ex that I came up with to match this is failing. Please help. (3 Replies)
Hi ,
I am facing a problem .. which looks simple... but took 2 days of mine.. even now it is not solved completely..
I have one variable..., want to know whether that variable contains number... canbe +ve or -ve ...
Values
+35 --- number
-43 --- number
45A -- non number... (12 Replies)
Hi,
I have one file like 00123. And this file name is generated as a sequence.
So how can I confirm the generated file name is a number, not a special character or alphabets.
Can anybody help me out.
Thanks in advance. (3 Replies)
Hi,
I have a file with data as given
$cat file1.txt
123
234
23e
234.456
234.876e
345.00
I am checking if the values are proper integers using the command.
nawk -F'|' 'int($1)!=$1 {printf "Error in field 1|"$0"\n"}' file1.txt
This is checking for only integers ( without... (10 Replies)
I have 2 and three params, both I should make sure thay numbers at one single line insted of checking for each one .
Example I wroote the following way.. checking for 2 and three seperately but I shud be able to do it at on statement
echo $2 | egrep '^+$' >/dev/null 2>&1
if ; then
echo... (2 Replies)
Dear Perl users,
I need your help to solve my problem below.
I want to print the sequence number without missing number within the range.
E.g. my sequence number :
1 2 3 4 5 6 7 8 11 12 13 14
my desired output:
1 -8 , 11-14
my code below but still problem with the result:
1 - 14
1 -... (2 Replies)
Hi Experts,
I am checking how to get day in Perl.
If it is “Monday” I need to process…below is the pseudo code.
Can you please prove the code for below condition.
if (today=="Monday" )
{
while (current_time LESS THAN 9:01 AM)
... (1 Reply)
Hi,
We are getting a curios result in one of AIX script. Its executed using !/bin/ksh .
After following line we get result of 3 in in the variable instance_count.
instance_count=`ps -ef | grep "script_check_instances.sh" | grep -v "grep" | wc -l`
But once we do a "ps -aef | grep... (2 Replies)
My issue is that the perl script (as I have done it so far) created empty branches when I try to check some branches on existence.
I am using multydimentional hashes: found it as the best way for information that I need to handle. Saing multidimentional I means hash of hashes ... So, I have
... (2 Replies)
Discussion started by: alex_5161
2 Replies
LEARN ABOUT DEBIAN
shell-quote
SHELL-QUOTE(1p) User Contributed Perl Documentation SHELL-QUOTE(1p)NAME
shell-quote - quote arguments for safe use, unmodified in a shell command
SYNOPSIS
shell-quote [switch]... arg...
DESCRIPTION
shell-quote lets you pass arbitrary strings through the shell so that they won't be changed by the shell. This lets you process commands
or files with embedded white space or shell globbing characters safely. Here are a few examples.
EXAMPLES
ssh preserving args
When running a remote command with ssh, ssh doesn't preserve the separate arguments it receives. It just joins them with spaces and
passes them to "$SHELL -c". This doesn't work as intended:
ssh host touch 'hi there' # fails
It creates 2 files, hi and there. Instead, do this:
cmd=`shell-quote touch 'hi there'`
ssh host "$cmd"
This gives you just 1 file, hi there.
process find output
It's not ordinarily possible to process an arbitrary list of files output by find with a shell script. Anything you put in $IFS to
split up the output could legitimately be in a file's name. Here's how you can do it using shell-quote:
eval set -- `find -type f -print0 | xargs -0 shell-quote --`
debug shell scripts
shell-quote is better than echo for debugging shell scripts.
debug() {
[ -z "$debug" ] || shell-quote "debug:" "$@"
}
With echo you can't tell the difference between "debug 'foo bar'" and "debug foo bar", but with shell-quote you can.
save a command for later
shell-quote can be used to build up a shell command to run later. Say you want the user to be able to give you switches for a command
you're going to run. If you don't want the switches to be re-evaluated by the shell (which is usually a good idea, else there are
things the user can't pass through), you can do something like this:
user_switches=
while [ $# != 0 ]
do
case x$1 in
x--pass-through)
[ $# -gt 1 ] || die "need an argument for $1"
user_switches="$user_switches "`shell-quote -- "$2"`
shift;;
# process other switches
esac
shift
done
# later
eval "shell-quote some-command $user_switches my args"
OPTIONS --debug
Turn debugging on.
--help
Show the usage message and die.
--version
Show the version number and exit.
AVAILABILITY
The code is licensed under the GNU GPL. Check http://www.argon.org/~roderick/ or CPAN for updated versions.
AUTHOR
Roderick Schertler <roderick@argon.org>
perl v5.8.4 2005-05-03 SHELL-QUOTE(1p)