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Full Discussion: Trivial perl doubt about FILE
Top Forums Shell Programming and Scripting Trivial perl doubt about FILE Post 302542626 by getmmg on Thursday 28th of July 2011 07:56:53 AM
Old 07-28-2011
Quote:
Originally Posted by royalibrahim
Hi,

In the following perl code:

Code:
#!/usr/bin/perl -w
 
if (open(FILE, "< in_file")) {
    while (<FILE>) {
        chomp($_);
        if ($_ =~ /patt$/) {
            my $f = (split(" ", $_))[0];
            print "$f\n";
        }
    }
    close FILE;
}

Why changing the "FILE" as "$FILE" gives error in the while loop and in the close statement?

FILE is the name of the file handle,
in_file is the name of the file you are trying to read.
 

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LEARN ABOUT SUSE

pfunc

PFUNC(1)						User Contributed Perl Documentation						  PFUNC(1)

NAME

       pfunc - grep for perl functions

SYNOPSIS

	   pfunc subroutine FILES...

DESCRIPTION

       pfunc searches the named FILES for all calls to the given subroutine.  It will report back the file and line number each call is found on
       along with what sort of call it is

	   function	       foo()
	   class method        Class->foo()
	   object method       $obj->foo()

EXAMPLE

	   $ pfunc isa /usr/share/perl/5.6.1/*.pm
	   Called as function in /usr/share/perl/5.6.1/CGI.pm at line 316
	   Called as function in /usr/share/perl/5.6.1/CGI.pm at line 327
	   Called as function in /usr/share/perl/5.6.1/CGI.pm at line 397
	   Called as function in /usr/share/perl/5.6.1/CGI.pm at line 494
	   Called as function in /usr/share/perl/5.6.1/CGI.pm at line 495
	   Called as object method in /usr/share/perl/5.6.1/CPAN.pm at line 4957
	   Called as function in /usr/share/perl/5.6.1/Dumpvalue.pm at line 191
	   Called as function in /usr/share/perl/5.6.1/Dumpvalue.pm at line 218
	   Called as function in /usr/share/perl/5.6.1/Dumpvalue.pm at line 248
	   Called as function in /usr/share/perl/5.6.1/Dumpvalue.pm at line 251
	   Called as function in /usr/share/perl/5.6.1/Dumpvalue.pm at line 254
	   Called as object method in /usr/share/perl/5.6.1/Shell.pm at line 28
	   Called as object method in /usr/share/perl/5.6.1/base.pm at line 12

NOTES

       Its not fast, but its accurate.

AUTHOR

       Michael G Schwern <schwern@pobox.com>

SEE ALSO

       Module::Info

perl v5.12.1							    2002-12-05								  PFUNC(1)
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