Difference Time Unix Shell

Shell Programming and Scripting
1

I have 2 variables

MTIME="Jan_2_2012_23:55:49"
SCH_TIME="Jan_03_2012_00:32:28"

I want to find the time taken (in seconds) between MTIME and SCH_TIME.

Is there any way by which this can be done in Unix Shell Script?

2

If your date supports -d option, try this...

#!/bin/bash

MTIME="Jan_2_2012_23:55:49"
SCH_TIME="Jan_03_2012_00:32:28"

((DIFF=$(date -d "${SCH_TIME//_/ }" +%s ) - $(date -d "${MTIME//_/ }" +%s )))
echo "$DIFF Seconds"

--ahamed

3

Thank you Ahamed.
But this works only in Linux.

Is there a way of using it in Solaris (ksh)

4

A perl:

#!/usr/bin/perl

use strict;
use Time::Piece;
use POSIX qw(strftime);

# Time::Piece to create two time objects using the timestamps  

my $MTIME="Jan_2_2012_23:55:49";
my $SCH_TIME="Jan_03_2012_00:32:28";

my $before = Time::Piece->strptime($MTIME   , "%b_%d_%Y_%H:%M:%S");
my $after  = Time::Piece->strptime($SCH_TIME, "%b_%d_%Y_%H:%M:%S");


# Gap in seconds
my $secdiff = int ($after - $before);

print "Seconds:$secdiff\n";


# Format the result .
print  strftime( '%H:%M:%S', gmtime($secdiff))."\n";
5

A solution in nawk

nawk 'BEGIN{
  MTIME="Jan_2_2012_23:55:49"; SCH_TIME="Jan_03_2012_00:32:28"

  month="JanFebMarAprMayJunJulAugSepOctNovDec"
  split(MTIME,a,"[_:]"); split(SCH_TIME,b,"[_:]")
  
  t1=mktime(a[3]" "int((index(month,a[1])/3))+1" "a[2]" "a[4]" "a[5]" "a[6])
  t2=mktime(b[3]" "int((index(month,b[1])/3))+1" "b[2]" "b[4]" "b[5]" "b[6])

  print t2-t1" Seconds"
}'

--ahamed