Loop through Arguments: for

Sometimes we may want to loop through a list of files executing some commands on each file. The for loop is used for this purpose:

 
for variable in list   	   
do   	   
    statement   	Execute statement on each loop.   
done   	Close the do with done.   

If the list option is not given, the for condition loops over the arguments to the shell script.

Now we run bigmat with file names as arguments to the shell command:

 
#!/bin/sh   	   
if [ $# -ne 1 ]   	   
then   	   
  echo "This script needs at least one argument."   	   
  exit -1   	   
fi   	   
for file   	Loop over the arguments.   
do   	   
  echo "Running program bigmat with input $file."   	   
  bigmat < $file   	Variable file contains the next argument.   
done   	   
exit