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Understand a old unix shell script

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# 1  
Old 02-10-2011
Understand a old unix shell script
Hi All,
I have a unix old script i but i am not able to understand the few commands in it and what it does. below is the script.
Code:
 if [ -f /ITF_*.dat ];
  then 
     for F in $(find $DIR/. ! -name . -prune -name "DP_*.dat")  
    do
     IN=${F##/*/}
     OUT='ORD'$(echo $IN | cut -c7-)
    exec.ksh $IN $OUT
     if [ $? -ne 0 ]; then
       exit 1
     fi
   done

I am not able to understand what does this script code part does and also what does the below command does.
1. if [ -f /ITF_*.dat ];
2. IN=${F##/*/}

Can you please let me know.
# 2  
Old 02-10-2011
1. if any files exist that match ITF_*.dat in the root (/) directory.
2. For an absolute path (one beginning with /), will remove the path, leaving just the filename. i.e. removes everything (*) starting from / and ending in /)

Code:
${parameter##word}
              The word is expanded to produce a pattern just as in pathname expansion.  If  the  pattern  matches  the
              beginning of the value of parameter, then the result of the expansion is the expanded value of parameter
              with the shortest matching pattern (the ``#'' case) or the longest matching pattern  (the  ``##''  case)
              deleted.

test man page
bash man page (search for Parameter Expansion)
This User Gave Thanks to Scott For This Post:
kam786sim
# 3  
Old 02-10-2011
1) Is testing whether there is at least on file (-f) in the root directory "/" which matches the pattern "ITF_*.dat". The asterisk is a wild card and the underscore and full stop characters are part of the name of the file.

2) Is doing the same as the "basename" unix command on the filename in parameter $F . It is removing any leading path information to leave the name of the file only.
This is a Shell function. Just search your Shell manual for the string "##" to read about it.
This User Gave Thanks to methyl For This Post:
kam786sim
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