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Full Discussion: Perl - backticks v system in if statements
Top Forums Shell Programming and Scripting Perl - backticks v system in if statements Post 79740 by ErNci on Sunday 31st of July 2005 06:25:47 AM
Old 07-31-2005
Yes, as tjlist said, the percecitonal way really should be

if ( ( system("/bin/chio -f $changerDevice move slot ".($tape-1)." drive 0
") ) / 256 ) {
print "$progname: cannot '/bin/chio -f $changerDevice move' tape
$tape into drive 0\n";
exit(2);
}
print LOG &do_time(), ": leave: Load\n";

And in the first example, the 2nd example would be

sub getDate {
print "start date\n";
my $buff = '';
if ( ($buff = `/bin/date`) eq ''){
print "can't get date\n";
exit(2);
}
print "finish date\n";
}
 

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LEARN ABOUT CENTOS

dm_date

DM_DATE(1)						User Contributed Perl Documentation						DM_DATE(1)

NAME

       dm_date - print out the system date and time

SYNOPSIS

       This performs the same operation as the unix 'date' command, but using the Date::Manip module.

	  dm_date [OPTION]... [+FORMAT]

DESCRIPTION

       This displays information about the current system time, or some other time. Options are:

       -h, --help
	   Print online help.

       -d STRING, --date=STRING
	   Display time described by STRING. STRING can be any string which can be parsed by Date::Manip.  Please refer to the Date::Manip::Date
	   documentation for details.

       -f DATEFILE, --file=DATEFILE
	   This reads each line in DATEFILE, and extracts a date from it and prints out the information.

	   Blank lines and lines starting with a pound (#) are ignored. Lines not containing a valid date are also ignored.

       -r FILE, --reference=FILE
	   Displays the last modification time of FILE.

       -R, --rfc-2822
	   Displayc the date and time in RFC 2822 format.

	   Example: Mon, 07 Aug 2006 12:34:56 -0600

       -u, --utc, --universal
	   Converts the date to UT (GMT) and prints out the information.

       Only one of -d, -f, or -r should be included. If more than one is included, the first one from the list (-d, -f, -r) is used and any other
       is ignored.

       The format string starts with a plus (+) and contains any of the format directives described in Date::Manip::Date.

KNOWN BUGS

       None known.

BUGS AND QUESTIONS

       Please refer to the Date::Manip::Problems documentation for information on submitting bug reports or questions to the author.

SEE ALSO

       Date::Manip::Date

LICENSE

       This script is free software; you can redistribute it and/or modify it under the same terms as Perl itself.

AUTHOR

       Sullivan Beck (sbeck@cpan.org)

perl v5.16.3							    2014-06-09								DM_DATE(1)
All times are GMT -4. The time now is 05:16 AM.
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