Shell Programming and Scripting

I would like to write a shell script which will read a list of filenames(with absolute paths) from a file and then determine the just filename component (without the absolute path and the file extension) and the file extension (if any)

The example list of filenames are as below :

/home/mark.williams/a.java
/usr/local/bin/perl
/usr/local/bin/gtar
/usr/local/packages/abcd.efgh.ijkl.mnop.xml

So the filenames may or may not have extensions and also, the filenames might have special characters like ".", "_" embedded in them.

Any help will be really appreciated!

so where is your shell script?
here's mine:

Code:

awk 'BEGIN{FS="/"}{print $NF}' file

Here is my script

for cfilename in `cat filelist.txt | sort -u`
do
file_extension=`echo $cfilename | awk -F\/ '{print $NF}' | awk -F. '{print $NF}'`
export file_extension
filename=$(basename $cfilename | awk -F. -v OFS=. '{$NF=""; sub("[.]$", ""); print}')
export filename
filename_w_ext=$filename.$file_extension
export filename_w_ext
done

But the problem this script craps out when it encounters files with NO extensions e.g. /usr/local/bin/perl
So I have to make it little more robust to handle these scenarios where filenames having no extensions can also exist.

I guess, your script just returns the last field (NF) of the record, which unfortunately doesn't solve my problem. But thanks for responding to my post.

For filenames with no embedded new lines:

Code:

$ cat infile
/home/mark.williams/a.java
/usr/local/bin/perl
/usr/local/bin/gtar
/usr/local/packages/abcd.efgh.ijkl.mnop.xml

$ while read;do f="${REPLY##*/}";echo "${f%.*}";done<infile
a
perl
gtar
abcd.efgh.ijkl.mnop

With zsh:

Code:

while read;do print "$REPLY:t:r";done<infile

If your filenames have no embedded spaces or other pathological characters:

With zsh:

Code:

set -- $(<infile)
print -l "$@:t:r"

And if your extension is .tar.gz?

Thanks for your reply!

Your solution works fine to get the filename componet (without the extension) and so does mine.

My problem is getting the file extension (especially returning null when there is no extenson per se e.g. /usr/local/bin/perl) That's the part which I am struggling with.

Also, if the file is /tmp/abcde.tar.gz, I would like to return "gz" as the extenion.

Could you post the expected output?

Code:

while read mLine
do
  mNameAndExt=`basename $mLine`
  mName=`echo $mNameAndExt | sed 's;\(.*\)\..*;\1;'`
  if [ ${#mNameAndExt} -eq ${#mName} ]; then
    mExt=''
  else
    mExt=`echo $mNameAndExt | sed 's/.*\.//'`
  fi
done < input_file