Hi,
I am working on device drivers.Once If register a device i'll get one major no. If i unregister and register again i'll get a different major no.What i have to do to get same major no. each time :( (0 Replies)
Hello, I have 2 hp-ux both running 11.23, I have move one of a harddisk from "UNIX A" to "UNIX B", so how can I read back the data in "UNIX B"?
Thanks (5 Replies)
I'm currently using zsh. Sometimes I find myself wishing to reuse an argument from earlier in the command.
I know that I can, of course, assign an argument to a variable ahead of time, and then easily use that variable more than once.
I know about the ability to reuse arguments from previous... (0 Replies)
Hello everyone.
I'm trying to create a conf file with variables that my other scripts will use.
I have several scripts that use the same variables, and since I don't know how to read them from an external file, i define them in each script (and then if i want to change one's value i need to... (4 Replies)
I have a LUN (From HP-Storage VA7110) that is claimed on 2 servers, but is in used in one of the VG on Server-1 .
Now I want to shut Server-1 and re-use that LUN on server-2 .
Server-1
Path-1 : /dev/rdsk/c4t0d1
Path-2: /dev/rdsk/c6t0d1
Server-2
Path-1: /dev/rdsk/c5t0d1
Path-2:... (8 Replies)
Hi
I am trying to write a shell script and wanted to re-use the value which I have entered already.
Here is the sample code.
echo "Enter Value : \c" ; read val
echo "Enter number: $val\c" ; read num
Now I wanted to change the value as showing in 2nd Line or if I will use enter, it... (15 Replies)
Greetings.
First of all I consider myself a newbe in Linux, that's why I'm seeking your help so please be patient!
I was given an old server (Solaris) that has Oracle (10.2.0) installed with a few databases. I'm supposed to reuse this server for this new application which will process data... (11 Replies)
I have a collection of format strings for sscanf, such as
"%02d%*1s%02d%*1s%02d"
to read in certain formatted strings, such as dates, times, etc.
I wonder if there is a way to use them in printf without some changes? The example above would not work - at least I can't think of any ways to... (4 Replies)
Discussion started by: migurus
4 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)