Shell Programming and Scripting

Hi Experts,


I have binary files contain an ID Line as:

:
:
$Header: FNDSCMON.fmb 115.6 2000/01/11 10:26:10 pkm ship$
:
:

where the ID Line format is:
$Header: <File_Name> <Version> <Last_update_date_time> pkm ship$

In this Example:
File_Name = FNDSCMON.fmb
Version = 115.6
Last_update_date_time = 2000/01/11 10:26:10


I want to write a script to update the ID Line as:
File_Name = the file name
Version = old_version + 0.1
Last_update_date_time = current date_time

so, the new ID line should be show as:
:
:
$Header: <the file name> <old_version + 0.1> <current date_time> pkm ship$
:
:

Can anyone help?

Thanks!


Victor Cheung

This should do the job:

Code:

#!/bin/sh

curr_dat=`date "+%Y\/%d\/%m"`
curr_time=`date "+%H:%M:%S"`

awk -v ver="old_version + 0.1" -v dat=$curr_dat -v t=$curr_time '
/^\$Header:/{$2=FILENAME;$3=ver;$4=dat;$5=t}1
' file

Regards

Hi Frank,

Sorry, I think I have uncompleted mentions of my question, here is the complete one, can you please help? :

I have binary files contain an ID Line as:

:
:
$Header: FNDSCMON.fmb 115.6 2000/01/11 10:26:10 pkm ship$
:
:

where the ID Line format is:
$Header: <File_Name> <Version> <Last_update_date_time> pkm ship$

In this Example:
File_Name = FNDSCMON.fmb
Version = 115.6
Last_update_date_time = 2000/01/11 10:26:10


I want to write a script to update the ID Line as:
File_Name = the file name
Version = version + 0.1
Last_update_date_time = current date_time

so, the new ID line should be show as:
:
:
$Header: <the file name> <version + 0.1> <current date_time> pkm ship$
:
:


- The line starts with "$Header:" and ends with "pkm ship$"
- The new line length have to be kept as same as the old line length (the whitespaces is adjustable)
- perl should be used for the replacment action (The files I want to change are binary files, using other command, such as, sed will make the file unusable)

Can you help how to write the script?


Many Thanks!
Victor Cheung

In that case you have to provide more information, what is the exact length of the fields, beginning in what position?

Regards

Hi Frank,

The exact length between the Start Pattern,$Header:, and the End Pattern,pkm ship$, is fixed to 80 characters,

e.g.1:
$Header: FNDSCMON.fmb 115.6 2000/01/11 10:26:10........................pkm ship$

could be changed as :

$Header: FNDSCMON.fmb 115.7 2008/04/21 13:29:09........................pkm ship$


or, e.g.2:
Other Word $Header: FNDSCMON.fmb 115.6 2000/01/11 10:26:10........................pkm ship$

could be changed as :

Other Word $Header: FNDSCMON.fmb 115.7 2008/04/21 15:36:50........................pkm ship$




p.s. please replace the .... as whitespaces, multi whitespaces will be trunced when posted to this forum, so I use .... instead.



Many Thanks!
Victor Cheung

Try this:

Code:

#!/bin/sh

curr_dat=`date "+%Y\/%m\/%d"`
curr_time=`date "+%H:%M:%S"`

awk -v dat=$curr_dat -v t=$curr_time -v name="old_version" -v ver="0.1" '
/^\$Header:/{
$2=sprintf("%-12s",name)
$3=sprintf("%-5s",ver)
$4=sprintf("%-10s",dat)
$5=sprintf("%-31s",t)
}1
' file

Regards

Code:

perl -pe 's!(\$Header: \S+ )(\d+\.\d+) (\d{4}/\d{2}/\d{2} \d{2}:\d{2}:\d{2})( +pkm ship\$)\n!
    my ($head, $ver, $date, $tail) = ($1, $2, $3, $4);
    my @now = gmtime();
    sprintf "%s %3.1f %04i/%02i/%02i %02i:%02i:%02i%s\n",
      $head, $ver+0.1, $now[5]+1900, $now[4]+1, $now[3], $now[2], $now[1], $now[0], $tail !e' file

... assuming you want the date stamp in GMT (you probably do, even if you think you don't).

The version will monotonously grow by 0.1 for each update; so after 115.9 you get 116.0, 116.1, etc. Hope you won't need to go beyond 999.9 because this code won't handle that (without wrecking the fixed-length constraint).

I don't have anything really to test this on, but report back if it doesn't work.