Shell Programming and Scripting

1) I have to create 3 scripts which create different output files. Script one creates datafiles, script2 creates control files and script3 creates flg files. The business wants the same timestamp to be attached to all the files created by these scripts.

Script1- Create data files - Data files name format-> xxxx.01122010_223048.dat
Script2- Create Control files - Control files name format -> yyyy.01122010_223048.ctl
Script3 - Create flg files- flg files name format-> zzzz.01122010_223048.flg


How can I define a variable which gives the timestamp once and then can be used in all the three scripts?

These scripts are called from an intial script as follows
./$POS_SCRIPT/dw_postodw_pharmacysplit.ksh
./$POS_SCRIPT/dw_postodw_controlfile.ksh
./$POS_SCRIPT/dw_postodw_cpfiles.ksh

How do I check the return status of the previous script before starting the next If the return status is not success, I need to write that to a logfile and exit in the succeeding scripts.
-----------------------------------------

2)I have an input file(named common_files) which contains a set of table names. I need to search the current directory to check if the filename contain the table names from the input file. Move all those files to another directory.

For example the filename is of the format XXXX_<tablename>_timestamp. If the tablename matches from input file, those files should be moved to another directory.

Can I do the grep and move with a single command in my scripting? I got stuckup as below.

Code:

if [[ -s common_files]]
then
while read line 
do 
 
'grep -l $line * | mv 
done <common_files 
fi

INPUT FILE -> a file contains a list of 450 pharmacyids
flat FILE -> 119 files whcih may conatin the 450 pharmacy ids , but position of ids vary
OUTPUT FILES->the files created from flat files by copying the matching lines for each id.

The below one is my script. Can somebody review and give suggestions on logic and performance?(I heard 'cat' and grep used together will slow down the performance especially this may be executed 119 * 450 times).

Code:

for pharmacyf in `ls`
do
$tablename=` $pharmacyf | cut –f3 -d'.' `
 
while read pharmacyid
do
cat $pharmacyf | grep -w $pharmacyid >> $POSOUT/ODS.POS.$pharmacyid.$tablename.$CURRENT_DATE
 
done<inputfile
done

Thanks
Maya

Moderator's Comments:

Use code tags and maybe indention please.

Those are some long questions
I'll attempt the first. It sounds fairly simple.
You need to get the current time stamp in your initial script and pass that as an argument to your 3 scripts.

Code:

TIMESTAMP=`date +%H%M%S`
#Or whichever format you prefer it in
./$POS_SCRIPT/dw_postodw_pharmacysplit.ksh $TIMESTAMP
./$POS_SCRIPT/dw_postodw_controlfile.ksh $TIMESTAMP
./$POS_SCRIPT/dw_postodw_cpfiles.ksh $TIMESTAMP

In each of these 3 scripts, you would write:

Code:

TIMESTAMP=$1

That should give you the common time stamp throughout all 3 scripts.

Regarding your second sub question, error handling should be done within the files itself. If you encounter an error, you could choose to exit with a specific error code (You can have an error code to error text mapping somewhere).

Something like:

Code:

exit 1

You can handle the return status best in your initial script itself.

Code:

TIMESTAMP=`date +%H%M%S`
#Or whichever format you prefer it in
RETURN_CODE=`$POS_SCRIPT/dw_postodw_pharmacysplit.ksh $TIMESTAMP`
if [ $RETURN_CODE -ne 0 ]
then
#ECHO ERROR TO LOG FILE
fi
RETURN_CODE=`$POS_SCRIPT/dw_postodw_controlfile.ksh $TIMESTAMP`
if [ $RETURN_CODE -ne 0 ]
then
#ECHO ERROR TO LOG FILE
fi
RETURN_CODE=`$POS_SCRIPT/dw_postodw_cpfiles.ksh $TIMESTAMP`
if [ $RETURN_CODE -ne 0 ]
then
#ECHO ERROR TO LOG FILE
fi

Thank you so much.

Maya