Working in a bash environment, in the following example, how do I direct the error message that putting in an invalid flag (-j for example) would normally produce to dev/null?
while getopts "abcd" opt
do
case "$opt" in
i) a etc ;;
r) b etc ;;
f) c etc ;;
v) d... (7 Replies)
can you redirect STDIN with command arguments?
I have tried this approach:
# ./script -option <argument1> <argument2> 0<$2
# $2: ambiguous redirect
Is this possible? (4 Replies)
Consider:
#!/bin/sh
#this is a shell script in sh (bourne)
grep missingfile 2>errout.txt
It works from the command line, but keeps producing errors from the script. So how do I redirect in a bash shell...or bourne? (3 Replies)
For windows was pretty simple to redirect the std in a and out of a
child process for "cmd.exe " command prompt terminal to a socket using connected pipes passed to a new process in the STARTUPINFO structure.
BOOL b = ::CreatePipe((LPHANDLE)h_stdInRead,(LPHANDLE)hsdtInWriteTmp, &SecAttrib,... (1 Reply)
Hi:
I have the next script on ksh
#!/usr/bin/ksh
cd $FUENTES
qdesign <<-!
\$/opt/cognos/ph843e/bin/qtp <<-!
\$/opt/cognos/ph843e/bin/quiz <<-!
!
!
!
This script is very simple, i want to nest three process quiz into qtp, and this into qdesign.
When I run it , i receive the... (5 Replies)
Hi:
I have the next script on ksh
#!/usr/bin/ksh
cd $FUENTES
qdesign <<-!
\$/opt/cognos/ph843e/bin/qtp <<-!
\$/opt/cognos/ph843e/bin/quiz <<-!
!
!
!
This script is very simple, i want to nest three process quiz into qtp, and this into qdesign.
When I run it , i receive the next... (2 Replies)
I am unable to use STDIn redirection with < (commands)
When I do the following, both approaches work and give the same results:
1.
$ printf "aaa\nbbb\n" > file1
$ printf "111\n222\n" > file2
$ cat file1 file2
aaa
bbb
111
2222.
$ cat <(printf "aaa\nbbb\n") <(printf "111\n222\n")
aaa... (8 Replies)
Looking for the proper way to bring a string into the stdin. I have a string that I would like to grep and awk. Each have to be run separately, not piped together. So far, the only way I could figure out how is to echo the string and pipe it:
echo 'This is my string' | grep my (3 Replies)
I want to differentiate the STDOUT and STDERR messages in my terminal .
If a script or command is printing a message in terminal I want to differentiate by colors,
Is it possible ?
Example:
$date
Wed Jul 27 12:36:50 IST 2011
$datee
bash: datee: command not found
$alias ls
alias... (2 Replies)
Hi, I'm running a program (Python) whose output I would like to redirect to a log. But the program calls a library (that I cannot change), which outputs all sorts of useless information.
I would like to redirect all output from my Python program into this log, except output that matches the... (7 Replies)
Discussion started by: rswindle
7 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)