Hi,
May I know how to check for empty file in Perl.
Iam missing something, somewhere.
#!/usr/bin/perl
my $open_dir = '/path/';
my $file;
my $ma = "abc_.*.\.psv\$"
opendir(VAR, $open_dir) or die "Can't open $oepn_dir: $!\n";
while( defined ($file = readdir VAR) ) #read all... (1 Reply)
Hi Masters.....
I have problem !!!
I need to check number of records in a file and if it is zero or file is empty i need to do some task.
if ; then
echo "File s empty"
else
echo "Not empty"
fi
so how to check this condition.
I used wc -l < filename.txt => 1 for zero records
same result... (1 Reply)
I need to check if $1 or $2 are empty before continuing but I don't know if bash has any logic of the sort. This is what I'm looking for - except that "and" doesn't seem to work.
if and ;then
...
Thank you! :D (4 Replies)
Hi All,
I am new to unix worldd .
I need to check a file1 if its empty or not.
If its empty then return a non zero value say 99
could you pls let me know the perl script for this. (2 Replies)
How do I check if a file is empty in a sh script
I want to test in my shell script if the output file is empty and if it is do one thing and if it isnt empty do another?
any ideas? (8 Replies)
Hello,
I want to checkl whether my file has text in it or not.
if ; then
...
if ; then
...
But none of these work
Can someone help me?
---------- Post updated at 09:00 AM ---------- Previous update was at 08:55 AM ----------
The code-tags caused an displayerror,... (5 Replies)
I am running a C shell script. I have an output file from a previous step and I need to run "something" in the next step to check if the file is empty. If the file is empty, then the job script should finish EOJ. If the file is not empty then the job script should abend.
Please help
Thanks. (4 Replies)
Hello,
I want to make a script which says if a text file is empty or not.
I tried two ways of making it, but I have problems with both of them.
Now I think that the better way is the ls -s solution (considering that an empty text file has a 0 weight, because "cat file.txt" fails when file is... (4 Replies)
Hi gurus ,
I have two files and i want to perform different action based on the condition if both or either is empty
If
then
Do something
elif
then
do something
elif
then
do something
else
do something
fi
I have tried the below bt its not... (4 Replies)
Hi All,
I need to check a file whether it exists and also whether it is empty or not. I have a code for this but it is not working as per my requirement. Can anyone pls suggest me on this.
function funcFLSanityCheck
{
if
then
echo "${varFLSentFileListPath}/${varFLSentFileName}... (7 Replies)
Discussion started by: Arun1992
7 Replies
LEARN ABOUT CENTOS
shell-quote
SHELL-QUOTE(1) User Contributed Perl Documentation SHELL-QUOTE(1)NAME
shell-quote - quote arguments for safe use, unmodified in a shell command
SYNOPSIS
shell-quote [switch]... arg...
DESCRIPTION
shell-quote lets you pass arbitrary strings through the shell so that they won't be changed by the shell. This lets you process commands
or files with embedded white space or shell globbing characters safely. Here are a few examples.
EXAMPLES
ssh preserving args
When running a remote command with ssh, ssh doesn't preserve the separate arguments it receives. It just joins them with spaces and
passes them to "$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 v5.16.3 2010-06-11 SHELL-QUOTE(1)