Yes. Perl allows you to call things without the () if you really want to, and they did so here. How it would with them is:
So @ARGV is the input array, and {code block} is what it does to every element of the array in turn. It's given @ARGV[N] as its argument, and returns whatever you want to transform it into.
I'm not sure that's valid syntax for perl in general - shoving entire code blocks wherever - especially since that code block isn't executed immediately, but repeatedly called by map(). This seems like special behavior.
The steps in the { } block are:
Match $_ (i.e. @ARGV[N]) against /(.*)\//
Return $1, i.e. the bracketed section matched by the regex
Assign the returned value to output[N] ( implied, done internally by map() )
Once every element is parsed, it's returned as a list into join().
Hello ,
Please can someone tell me what exactly happens when the below filehandler is chomped into an array and later mapped.
$lcpLog="logcopy\@".getTimestamp."\log";
open CFg ,"< $lcpcfg";
chomp(@cfg = <CFG>);
close CFG;
@cfg=grep { $_ ne ' ' } map { lc + (split /\s*\/\//) }... (0 Replies)
There is a function called start:
start()
{
echo -n $"Sending Startup Email: "
echo "${RESTARTBODY}" | mutt -s "${RESTARTSUBJECT}" ${EMAIL}
RETVAL=$?
if ; then
touch ${LOCKFILE}
success
else
failure
fi
echo
return ${RETVAL}
}
Can anyone explain what the bold part of the... (3 Replies)
Hi guys,
I'm trying to learn grep and map and having a little problem.
Let's say I have a file which contains:
Apple: abcdcabdadddbac
I want to replace any combinations of three of abcd, thus when I do this:
print grep {s/{3}/X/g} <F>; # will do the subtitution fine, output XXXX
... (1 Reply)
Hi,
I have 2 arrays:
@names=qw(amith veena chaitra);
@files=qw(file.txt file1.txt file3.txt);
There is one to one relationship between names and files.
There needs to be mapping created between names and files.
The output should be like this:
amith --> file.txt
veena --->... (3 Replies)
Well, I found myself trying to fix some Perl code (Ive never done any Perl in my life) and I pinpointed the place where the bug could be. But to be sure I have to know what does a few line of code mean:
$files_lim =~ (/^\d*$/)
$files_lim =~ (/^\d*h$/)
$files_age =~ s/h//
The code where... (2 Replies)
Hi all,
I am trying to build threads which will go to localhost and list the files in given folder.
#!/usr/bin/perl
use threads;
my $t1 = threads->new(\&sub1, 1);
my $t2 = threads->new(\&sub2, 2);
push(@threads,$t1);
push(@threads,$t2);
foreach... (5 Replies)
Hello All,
I am writing the below script where it will connect to database and returns the results.
#!/sw/gcm/perl510/bin/perl
use SybaseC;
&openConnection;
&loadvalues;
sub openConnection {
$dbproc = new SybaseC(SYDB}, $ENV{DBDFLTUSR}, $ENV{DBDFLTPWD});
if... (2 Replies)
Hello,
I recently started going in depth with the shell, so I started learning from Linux Shell Scripting CookBook, 2nd edition. I am at the first chapter atm, and the author tells to define a function in the ~/.bashrc.
The function is below.
prepend() { && eval $1=\"$2':'\$$1\" && export... (1 Reply)
I have a file like
file.
file.TODAY.THISYEAR
file.TODAY.LASTYEARI want to substitute the words in caps with their actual values so that output should look like
file.140805
file.140805.2014
file.140805.2013For this I am reading the file line bye line in an array and using multiple map... (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 LINUX
dpkg::conf
Dpkg::Conf(3) libdpkg-perl Dpkg::Conf(3)NAME
Dpkg::Conf - parse dpkg configuration files
DESCRIPTION
The Dpkg::Conf object can be used to read options from a configuration file. It can exports an array that can then be parsed exactly like
@ARGV.
FUNCTIONS
my $conf = Dpkg::Conf->new(%opts)
Create a new Dpkg::Conf object. Some options can be set through %opts: if allow_short evaluates to true (it defaults to false), then
short options are allowed in the configuration file, they should be prepended with a single dash.
@$conf
@options = $conf->get_options()
Returns the list of options that can be parsed like @ARGV.
$conf->load($file)
Read options from a file. Return the number of options parsed.
$conf->parse($fh)
Parse options from a file handle. Return the number of options parsed.
$conf->filter(remove => $rmfunc)
$conf->filter(keep => $keepfunc)
Filter the list of options, either removing or keeping all those that return true when &$rmfunc($option) or &keepfunc($option) is
called.
$string = $conf->output($fh)
Write the options in the given filehandle (if defined) and return a string representation of the content (that would be) written.
"$conf"
Return a string representation of the content.
$conf->save($file)
Save the options in a file.
AUTHOR
Raphael Hertzog <hertzog@debian.org>.
1.16.0.3 2012-04-17 Dpkg::Conf(3)