compare_dates

来自「EM算法的改进」· 代码 · 共 132 行

#!/usr/bin/perl
#
# $Id: compare_dates.txt 1339 2006-09-21 19:46:28Z tbailey $
# $Log$
# Revision 1.1  2005/07/28 23:52:45  nadya
# Initial revision
#
#
# AUTHOR: Timothy L. Bailey
# CREATE DATE:

$PGM = $0;			# name of program
$PGM =~ s#.*/##;                # remove part up to last slash
@args = @ARGV;			# arguments to program
$| = 1;				# flush after all prints
$SIG{'INT'} = 'cleanup';	# interrupt handler
# Note: so that interrupts work, always use for system calls:
# 	if ($status = system($command)) {&cleanup($status)}

# requires
push(@INC, split(":", $ENV{'PATH'}));	# look in entire path

# defaults
%months = (Jan, "00", Feb, "01", Mar, "02", Apr, "03", May, "04", Jun, "05", 
  Jul, "06", Aug, "07", Sep, "08", Oct, "09", Nov, 10, Dec, 11);

$usage = <<USAGE;		# usage message
  USAGE:
	$PGM <mon1> <day1> <time1> <mon2> <day2> <time2>

	<mon>	Jan..Dec
	<day>	day 1..31
	<time>	time: hh:mm or year: yyyy

	Compare two dates and exit with status 1 if the second dates is
	larger (more recent) than the first, with status 0 otherwise.

	Copyright 
	(2001) Timothy L. Bailey 
        All Rights Reserved.
        Author: Timothy L. Bailey
USAGE

$nargs = 6;			# number of required args
if ($#ARGV+1 < $nargs) { &print_usage("$usage", 2); }

# get input arguments
$i = 0;
while ($#ARGV >= 0) {
  $_ = shift;
  if ($_ eq "-h") {				# help
    &print_usage("$usage", 2);
  } elsif ($i<6) {
    $input[$i++] = $_;
  } else {
    &print_usage("$usage", 2);
  }
}

#
# get todays date
#
($sec, $min, $hour, $mday, $mon, $year, @rest) = localtime(time);
$min = "0$min" if ($min < 10);
$hour = "0$hour" if ($hour < 10);
$mon = "0$mon" if ($mon < 10);
$day = $mday;
$year = 1900 + $year;
$date = "$year $mon $day $hour $min";

#
# construct the two dates from the input
#
for ($i=0; $i<2; $i++) {		# construct date i
  $_ = shift @input;			# get next word of inut
  $mon[$i] = $months{$_};
  $_ = shift @input;			# get next word of inut
  $day[$i] = ($_ >= 10) ? $_ : "0$_";
  $_ = shift @input;			# get next word of inut
  if (s/:/ /) {				# no year given
    $time[$i] = $_;
    # last year or this year?
    $year[$i] = ("$mon[$i] $day[$i]" gt "$mon $day") ? $year-1 : $year;
  } else {				# year given
    $time[$i] = "00 00";		# don't know the time
    $year[$i] = $_;
  }
  $date[$i] = "$year[$i] $mon[$i] $day[$i] $time[$i]";
} # construct date i

if ($date[0] lt $date[1]) { exit(1) } else { exit(0) }

# cleanup files
&cleanup($status);
 
################################################################################
#                       Subroutines                                            #
################################################################################
 
################################################################################
#
#       print_usage
#
#	Print the usage message and exit.
#
################################################################################
sub print_usage {
  my($usage, $status) = @_;
 
  if (-c STDOUT) {			# standard output is a terminal
    open(C, "| more");
    print C $usage;
    close C;
  } else {				# standard output not a terminal
    print STDERR $usage;
  }

  exit $status;
}
 
################################################################################
#       cleanup
#
#       cleanup stuff
#
################################################################################
sub cleanup {
  my($status, $msg) = @_;
  if ($status && "$msg") {print STDERR "$msg: $status\n";}
  exit($status);
}