[Solved] Check if file is empty with variables, bash
Hello again!
I have some trouble with scripting in bash.
In the following script I read from a folder with the files
Code:
line0_Ux.xy
line1_Ux.xy
line2_Ux.xy
.
.
.
Some of the files are empty. For those I would like to print a "0" in list.
I think the problem with the code is that bash thinks "$i_Ux" is the variable, but Im not sure..
Code:
for i in $( ls -v ); do
echo item: $i
if [ ! -s line$i_Ux.xy ]; then
echo -e "0" >> list
else
cat $i | awk '{a+=$2; n++;} END {print a/n}' >> list
done
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 DEBIAN
devel::refcount
Devel::Refcount(3pm) User Contributed Perl Documentation Devel::Refcount(3pm)NAME
"Devel::Refcount" - obtain the REFCNT value of a referent
SYNOPSIS
use Devel::Refcount qw( refcount );
my $anon = [];
print "Anon ARRAY $anon has " . refcount($anon) . " reference
";
my $otherref = $anon;
print "Anon ARRAY $anon now has " . refcount($anon) . " references
";
DESCRIPTION
This module provides a single function which obtains the reference count of the object being pointed to by the passed reference value.
FUNCTIONS
$count = refcount($ref)
Returns the reference count of the object being pointed to by $ref.
COMPARISON WITH SvREFCNT
This function differs from "Devel::Peek::SvREFCNT" in that SvREFCNT() gives the reference count of the SV object itself that it is passed,
whereas refcount() gives the count of the object being pointed to. This allows it to give the count of any referent (i.e. ARRAY, HASH,
CODE, GLOB and Regexp types) as well.
Consider the following example program:
use Devel::Peek qw( SvREFCNT );
use Devel::Refcount qw( refcount );
sub printcount
{
my $name = shift;
printf "%30s has SvREFCNT=%d, refcount=%d
",
$name, SvREFCNT($_[0]), refcount($_[0]);
}
my $var = [];
printcount 'Initially, $var', $var;
my $othervar = $var;
printcount 'Before CODE ref, $var', $var;
printcount '$othervar', $othervar;
my $code = sub { undef $var };
printcount 'After CODE ref, $var', $var;
printcount '$othervar', $othervar;
This produces the output
Initially, $var has SvREFCNT=1, refcount=1
Before CODE ref, $var has SvREFCNT=1, refcount=2
$othervar has SvREFCNT=1, refcount=2
After CODE ref, $var has SvREFCNT=2, refcount=2
$othervar has SvREFCNT=1, refcount=2
Here, we see that SvREFCNT() counts the number of references to the SV object passed in as the scalar value - the $var or $othervar
respectively, whereas refcount() counts the number of reference values that point to the referent object - the anonymous ARRAY in this
case.
Before the CODE reference is constructed, both $var and $othervar have SvREFCNT() of 1, as they exist only in the current lexical pad. The
anonymous ARRAY has a refcount() of 2, because both $var and $othervar store a reference to it.
After the CODE reference is constructed, the $var variable now has an SvREFCNT() of 2, because it also appears in the lexical pad for the
new anonymous CODE block.
PURE-PERL FALLBACK
An XS implementation of this function is provided, and is used by default. If the XS library cannot be loaded, a fallback implementation in
pure perl using the "B" module is used instead. This will behave identically, but is much slower.
Rate pp xs
pp 225985/s -- -66%
xs 669570/s 196% --
SEE ALSO
o Test::Refcount - assert reference counts on objects
AUTHOR
Paul Evans <leonerd@leonerd.org.uk>
perl v5.14.2 2011-11-15 Devel::Refcount(3pm)
09-19-2013
