In one of my scripts I do the following
sort +0 x > y
mv y x
In my script x and y are fully qualified. This works 99% of the time. However once in a while the system comes back and says that is cannot access y in the mv command.
I did some research and I suspect that if I insert a... (7 Replies)
Hi guys !!
well i'm still new in learning UNIX , and actually i'm still studying it by myself ..
anyway, some people told me the Bourne-again shell is a good version of UNIX to work on , and i tried to download yesterday but i didn't know how to start it ...... the ReadMe file associated with... (3 Replies)
Hi All,
Must be something obvious I am missing, but the simple script below doesn't work.
#!/bin/sh
x=4
if
then
echo "x is $x"
elsif
then
echo "x is greater than 4"
else
echo "x is less than 4"
fi
When I run this script, I get the error message:
7: Syntax error... (3 Replies)
Hi!
I have here a simple script to change the advskew on carp interfaces. The first is working, but the part for status, where a for is within a if/else delivers everyime only the action for the value "prod". Even when i use type test or dev. Where did i made the mistake?
# $Log:... (2 Replies)
I do not claim to be an expert, but I have done things with scripts that whole teams of folks have said can not be done. Of course they should have said we do not have the intestinal fortitude to git-r-done.
I have been using UNIX actually HPUX since 1992. Unfortunately my old computer died and... (7 Replies)
Hi All
I have writing a Korn Shell script to execute it on many of our servers. But some servers don't have Korn Shell installed, they use Borne Shell.
Some operations like calculation don't work :
cat ${file1} | tail -$((${num1}-${num2})) > ${file2}
Is it possible to activate Korn Shell... (3 Replies)
Here's the input:
alpha, numeric or alphanumeric string ("line 1 string")
numeric string ("line 2 string")
numeric string ("line 3 string")
numeric string ("line 4 string")
...
where
- each numeric string is in a pattern that can be matched with RE but
- there can be any number of... (2 Replies)
Exercise Five
Write a Bourne shell script which:
• Professionalism: plan for this from the start.
• Has one command line argument.
• If the command line argument is a directory then the script should output the number of
files in the directory.
• If the command line argument is an ordinary... (2 Replies)
Could some one tell me the difference btw Bourne shell and the Kshell? Which is more flexible and reliable in terms of portability and efficiency. When i type the following command ..
$ echo $SHELL
yields me
/bin/sh
Does this tells me that I am in Bourne shell. If yes, how can i get... (6 Replies)
A severe vulnerability was discovered in Bourne shell.
Just google for: bash vulnerability
... for more details. (5 Replies)
Discussion started by: Cochise
5 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)