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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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Data::Faker::DateTime(3pm)				User Contributed Perl Documentation				Data::Faker::DateTime(3pm)

NAME
Data::Faker::DateTime - Data::Faker plugin SYNOPSIS AND USAGE
See Data::Faker DATA PROVIDERS
unixtime Return a unix time (seconds since the epoch) for a random time between the epoch and now. date Return a random date as a string, using a random date format (see date_format). time Return a random time as a string, using a random time format (see time_format). rfc822 Return an RFC 822 formatted random date. This method may not work on systems using a non-GNU strftime implementation (kindly let me know if that is the case.) ampm Returns am or pm randomly (in the current locale) using one of the formats specified in ampm_format. time_format Return a random time format. date_format Return a random date format. ampm_format Return a random am/pm format. datetime_format Return a random date and time format. month Return a random month name, unabbreviated, in the current locale. month_abbr Return a random month name, abbreviated, in the current locale. weekday Return a random weekday name, unabbreviated, in the current locale. weekday_abbr Return a random weekday name, abbreviated, in the current locale. sqldate Return a random date in the ISO8601 format commonly used by SQL servers (YYYY-MM-DD). datetime_locale Return a datetime string in the preferred date representation for the current locale, for a random date. date_locale Return a date string in the preferred date representation for the current locale, for a random date. time_locale Return a time string in the preferred date representation for the current locale, for a random date. century Return a random century number. dayofmonth Return a random day of the month. UTILITY METHODS
Data::Faker::DateTime::timestr($format); Given a strftime format specifier, this method passes it through to POSIX::strftime along with a random date to display in that format. Perl passes this through to the strftime function of your system library, so it is possible that some of the formatting tokens used here will not work on your system. NOTES AND CAVEATS
Be careful build timestamps from pieces Be very careful about building date/time representations in formats that are not already listed here. For example if you wanted to get a date that consists of just the month and day, you should NOT do this: my $faker = Data::Faker->new(); print join(' ',$faker->month,$faker->dayofmonth)." "; This is bad because you might end up with 'February 31' for example. Instead you should use the timestr utility function to provide you a formatted time for a valid date, or better still, write a plugin function that does it: my $faker = Data::Faker->new(); print $faker->my_short_date()." "; package Data::Faker::MyExtras; use base qw(Data::Faker); use Data::Faker::DateTime; __PACKAGE__->register_plugin( my_short_date => sub { Data::Faker::DateTime::timestr('%M %e') }, ); POSIX::strftime See the documentation above regarding the timestr utility method for some caveats related to strftime and your system library. SEE ALSO
Data::Faker AUTHOR
Jason Kohles, <email@jasonkohles.com> COPYRIGHT AND LICENSE
Copyright 2004-2005 by Jason Kohles This library is free software; you can redistribute it and/or modify it under the same terms as Perl itself. perl v5.10.1 2005-07-14 Data::Faker::DateTime(3pm)
All times are GMT -4. The time now is 01:16 PM.
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