Hello There!
I am trying to write this SIMPLE script in Bourne Shell but I keep on getting syntax errors. Can you see what I am doing wrong? I've done this before but I don't see the difference. I am simply trying to take the day of the week from our system and when the teachers sign on I want... (7 Replies)
This "SHOULD" be a simple question,
but looking through several books has turned up nothing,
so I turn once again to the experts!!
How do you vi a file so that you can see special characters.
I believe my /etc/passwd file is being corrupted during an upgrade process, however the files... (6 Replies)
Hi, I am new to UNIX, and am learning from this tutorial : http://www.ee.surrey.ac.uk/Teaching/Unix/index.html
It keeps telling me to files downloaded from the internet (like .txt files) to the directory, and I dont know how to.
How do I add .txt files to my directory? Thanks. (6 Replies)
Hello all,
Quick question from a fairly new to Unix developer.
if
then
completedLogFile=$logfile.$(date +%Y%m%d-%H:%M:%S)
mv $logfile $completedLogFile
fi
I understand that this portion of code is simply copying a tmp logfile to a completed logfile when a condition is true. The... (2 Replies)
Hi,
At best I'm a junior admin with a big problem.
My developers have got my root password and mgmt insists they need it.
I can't even change it when people knowing it leave.
I'm certain they've hardcoded it into routines. I've searched my servers and grepped everything & can't find it.
... (5 Replies)
I am using sed to find a pattern in a line and then I want to retain the pattern + the rest of the line. How is this possible? ie:
line is: 14158 05-15-08 20:00 123-1234-A21/deliverable/dhm.a
search for 123-1234-A21 ie:
echo $line | sed 's/.*\(\{3\}-\{4\}-\{3\}\{5\}\).*/\1/'
... (1 Reply)
Hi guys
Quick question
Im creating an FTP server and im chrooting each user to there home directory blah blah. Ive also setup scponly so there locked etc.
Im a novice at unix and have just reaslised the primary group of scponly is the username of one of the ftp users... which im sure... (1 Reply)
Discussion started by: mokachoka
1 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)