UNIX for Dummies Questions & Answers

Hi all,

here is a problem,

i am having a data in a file of this format,

cat filename|grep -ivn edc|tr -s ' ' +|cut -d+ f1,12

1 01:18:38 2007
25 01:43:38 2007
48 01:58:45 2007
71 02:11:02 2007
102 02:19:51 2007
and so on ........ ....... .




here 1,25,48,71,102 are the line numbers of each info

01:18:38:2007 are the timings of each info generated



here i am trying to get the time difference i.e

time difference between 1 and 25 line time difference to be printed(i.e 01:18:38:2007 - 01:43:51 2007= 00:25:13)

again time difference between 25line and 48 (i.e 01:43:51 2007-01:58:45 2007=some value)

again time difference between 48 and 71 line (i.e 01:58:45 2007-02:11:02 2007=some value)...... and so on till the End of Line in filename.



so trying to write a script .....

waiting for ur valuable suggestions till then i will be going ahead with my trails....


Summary:
i want to get the time difference between each line info.....

for further clarification kindly let me know.





Thanks in Advance.

Write a function to convert the time in HH:MM:SS to seconds since midnight.
(HH*3600)+(MM*60)+SS)
Then subtract the two times.
Write a function to convert seconds since midnight to HH:MM:SS
Use remainder division:
HH=seconds/3600
MM=(seconds-(HH*3600))/60
SS=(seconds - (HH*3600)-(MM*60)

i had written a code to convert time of this format(01:40:38) to minutes as follows but looking for help how to complete as stated above (i.e the thread which i posted.... )



var=`echo "01:40:38 "`
echo "$var" | cut -d: -f1 > a1 ;
echo "$var" | cut -d: -f2 > a2 ;
echo "$var" | cut -d: -f3 > a3 ;
HH=`cat a1`;
Hours=$(($HH*3600));
MI=`cat a2`;
Minutes=$(($MI*60));
SS=`cat a3`
totseconds=$(($Hours+$Minutes+$SS))
echo $totseconds

So use the following as a skeleton for your script:

initialize variables
read first record into prev-record-variables
while read current-record
do
subtract prev-record data from current-record
display results
move current-record to prev-record
done

thanks jgt.....

i understood it but theoritically i feel uncomfortable to put into a scenario that gives the result

if possible will u please come out with a practical example considering the first thread as an example,