Because that's the syntax for terminating a block of case statements. The first semi-colon ends that particular statement and the second ends the whole case block. The second one ensures that you don't try the following case blocks.
It is also possible to try the following block/s if you replace the second semi-colon with an ampersand (I think that's called a fall-through).
produces
Hi,
Can anyone please let me know the meaning of this line,i am not able to understand the egrep part(egrep '^{1,2}).This will search for this combination in beginning but what does the values in {}signifies here.
/bin/echo $WhenToRun | egrep '^{1,2}:$' >/dev/null (1 Reply)
OS : SOLARIS 10
debug tool :$gdb -v
GNU gdb 6.6
compiler : $gcc -v
gcc version 2.95.3 20010315 (release)
When i tried to debug my application i got the following error.
$gdb Pal
GNU gdb 6.6
Copyright (C) 2006 Free Software Foundation, Inc.
This GDB was... (2 Replies)
If I don't explain my issue well enough, I apologize ahead of time, extreme newbie here to scripting.
I'm currently learning scripting from books and have moved on to the text Wicked Cool Shell Scripts by Dave Taylor, but there are still basic concepts that I'm having trouble understanding.
... (10 Replies)
i am beginner in shell scripting.
not able to understand what below line will do.
PS1=${HOST:=Žuname -nŽ}"$ " ; export PS1 HOST
below is the script
#!/bin/hash
PS1=${HOST:=Žuname -nŽ}"$ " ; export PS1 HOST ;
echo $PS1
and i getting the below output
Žuname -nŽ$ (25 Replies)
I have added some code in my file.
I have created executable rpm file of our code and also I have created debuginfo and debugsource files and installed all three.
But when I debug in gdb I see the the code changes in soucre file. But the break point does not hit at that place as if it did not... (1 Reply)
the attached perl script is a deamon that, once kicked off from the command line, it runs in the background and waits for the master server to tell it what plugins to run.
the script works well. but the problem is, whenever i start it, after about a few seconds of starting it, i start getting... (4 Replies)
Hi ,
could someone suggest best reference for core file understanding , analysis , debugging for different architectures
like what registers represent what in a architecture specific core ..
how to get maximum information out of corrupted core
different tools and how they work and how to... (1 Reply)
I have this code
#!/bin/bash
LZ () {
RETVAL="\n$(date +%Y-%m-%d_%H-%M-%S) --- "
return RETVAL
}
echo -e $LZ"Test"
sleep 3
echo -e $LZ"Test"
which I want to use to make logentrys on my NAS. I expect of this code that there would be output like
2017-03-07_11-00-00 --- Test (4 Replies)
Discussion started by: matrois
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)