unix shell script about converting files name to lower case

That doesn't matter as the script has #!/bin/sh as the first line. Simply copy the script in a file, give it execute permission and run it. It should display the warnings and mv command (doesn't execute it). If you are satisfied with the test, change the line

echo nv $file $filelower

to

mv $file $filelower

Yes there are several errors. Here is the updated script for c shell

#!/bin/csh

foreach file (*.cpp *.sh)
        if (-d $file) then
                echo "Warning: $file is Directory"
        else
                if (-f $file) then
                        set filelower=`echo $file | tr "[:upper:]" "[:lower:]"`
                        if ($file == $filelower) then
                                echo "$file : file name aready in lower case!"
                        else
                                if (-f $filelower) then
                                        echo "$file = with lower case in exist, cant convert to lower case"
                                else
                                        echo mv $file $filelower
                                endif
                        endif
                endif
        endif
end

Yes. You can use sed also exactly the way you have written. It is little longer in length compared to tr.

Is it listing all files? Probably not.

Change

foreach file (*.cpp *.sh)

to

foreach file (*.cpp *.h)

Ok. Is it listing all the files with extension .cpp and .h in that directory? It should list all of them even if some logic is incorrect. If so, give an example of its output that is incorrect.

You can make your csh script looks like:

#!/bin/csh

# use grep -v to get rid of all the dirs

foreach file ( `ls -al *.h *.cpp | grep -v ^d | awk '{print $9}' `)
   set newfile = `echo $file | tr "[:upper:]" "[:lower:]"`
   mv $file $newfile
end

exit

BTW, why not use ksh for script ? For shell scripting you should use sh/ksh/bash, it is a lot easy to do things than csh/tcsh.

please have a look at "Csh Programming Considered Harmful":
http://sc.tamu.edu/help/other/CshProgrammingConsideredHarmful.html

Run this and post the output...

#!/bin/csh

foreach file (*.cpp *.sh)
      echo "Proceesing $file ..."

        if (-d $file) then
                echo "Warning: $file is Directory"
        else
                if (-f $file) then
                        set filelower=`echo $file | tr "[:upper:]" "[:lower:]"`

                  echo "Lowercase name $filelower"

                        if ($file == $filelower) then
                                echo "$file : file name aready in lower case!"
                        else
                                if (-f $filelower) then
                                        echo "$file = with lower case in exist, cant convert to lower case"
                                else
                                        echo mv $file $filelower
                                endif
                        endif
                endif
        endif
end

what do you mean "is it is not listing them at all"? my previous script will convert all the *.h *.cpp filenames to lower case, if it is alread lower case, if
will make no convertion.

you can modify it to:

#!/bin/csh

# use grep -v to get rid of all the dirs

foreach file ( `ls -al *.h *.cpp | grep -v ^d | awk '{print $9}' `)
   set newfile = `echo $file | tr "[:upper:]" "[:lower:]"`
   if ( -e $newfile ) then
       echo " $newfile is already lower case name"
   else
      mv $file $newfile
   endif
end

exit


PS:
ls -al *.h *.cpp | grep -v ^d | awk '{print $9}'

give you a list of all the files (excluding dirs), you might need to add
cd /mydir
in the beginning of the script

BTW, you can add:

    echo "Proceesing $file ..."
   after foreach file ( `ls -al *.h *.cpp | grep -v ^d | awk '{print $9}' `)

   to get the list on your screen.

# somthing lke:
find . -type f -name \*.cpp|sort -r|awk '{f=tolower($1);if(f!=$1 && p[f]!=1){print "mv "$1" "f}p[$1]=1}'

# if this is what you want, then simply pipe the result to sh

find . -type f -name \*.cpp|sort -r|awk '{f=tolower($1);if(f!=$1 && p[f]!=1){print "mv -i "$1" "f}p[$1]=1}'