Does the rm command throw an error when ${vra} does not exist or does it simply proceed with a null byte or something followed by /* erasing everything in its path.
As a beginner in Linux / Bash everything seems to bring up a question.
Sir,
I using the following commands in a file (part of a bigger script):
#!/bin/bash
cd /opt/oracle/bin
ls -lt | tail -1 | awk '{print $6}' >> /tmp/ramb.out
If I run this from the command prompt the result is:
2007-05-16
if I run it as a cron job then... (5 Replies)
Hi everybody!
We have to upgrade serviceguard 11.14 to 11.16, so I get PHSS_36898 patch from HP.
Is it necessary to uninstall serviceguard 11.14 before install this patch? (I think so, but i am not sure).
Do you know if is "dangerous" this kind of upgrade? Any suggestions about?
Thx in... (1 Reply)
Hi ,
I have a piece of code ...wherein I need to assign the following ...
1) A command line argument to a variable
e.g origCount=ARGV
2) A unix command to a variable
e.g result=`wc -l testFile.txt`
in my awk shell script
When I do this :
print "origCount" origCount --> I get the... (0 Replies)
AIX:Command to get netaddress/subnet address command in IPv4/IP6
Can anybody help us with a command to retrieve netaddress/subnet address command in IPv4/IP6 on aix machine.
net/subnet address is in the format 172.16.212.0(signifies all 255 machines in an IPv4 network) (2 Replies)
I had a umount busy issue, that the usual fuser -mk did not solve, I did a umount -l and was able to unmount the device, I then got in trouble by the storage team staff:
Here was a snippet of their response:
Using "umount -l" is a potentially dangerous act.
The command combination for a lazy... (8 Replies)
Hi everyone,
when executing this command in unix:
echo "WM7 Fatal Alerts:", $(cat query1.txt) > a.csvIt works fine, but running this command in a shell script gives an error saying that there's a syntax error.
here is content of my script:
tdbsrvr$ vi hc.sh
"hc.sh" 22 lines, 509... (4 Replies)
Hello,
I have a Application which needs to run shell scripts in a elevated state (root) for system interrogation. So I execute each script using bash -C. This has worked really well.
I now want to add another layer of security, I cant inspect each of the scripts before they get deployed to the... (4 Replies)
HI Guys,
I hope you are well. I am trying to write a script that gets executed every time i open a shell (cshell). I have two questions about that
1) I need to enter these commands
$ echo $DISPLAY
$ setenv $DISPLAY output_of_echo_$display_command
How can i write a... (2 Replies)
Discussion started by: kaaliakahn
2 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)