Shell Programming and Scripting

Friends,

Thanks for your valuable inputs. Will try it out and let you know asap.. But i have a doubt on the command

Code:

tee /dev/tty

tee means creation of file. Could you please explain me that statement alone. So that it would be useful for me to understand the concept...

The tee utility does not "mean creation of file". The tee utility copies data read from its standard input to its standard output and also makes a copy of everything read from its standard input in all of the files named as operands. The special file /dev/tty is the process' controlling terminal. If you want to redirect the output of your this pipeline to a file, the command line would be:

Code:

ls -a |tee file | wc -l >> file

If you want long listing output (instead of just the file names), the command line would be:

Code:

ls -l | grep -v '^total' | tee /dev/tty | wc -l
        or
ls -l | grep -v '^total' | tee file | wc -l >> file

By default, the tee utility empties the files named by its operands before copying data to them; this doesn't matter for /dev/tty. If you want to save the output to a regular file and you want to append the data to the file instead of replacing data in the file, use:
ls -l | grep -v '^total' | tee -a file | wc -l >> file

Note that the total line in ls -l output is not the number of files in the directory; it the the number of disk blocks consumed by files in the directory. So, if you want long listing output, the grep -v gets rid of that total line, the tee command copies the remaining ls -l output to your destination file and also copies it to its standard output so wc -l can count the number of lines the ls command printed and adds that output to the end of the output written by the tee command.

Another way:

Code:

set -- *; [ -e "$1" ] && printf "%s\n" "$@" "Number of files: $#"

or to include hidden files/directories etcetera including "." and "..""

Code:

set -- .* *; [ -e "$1" ] && printf "%s\n" "$@" "Number of files: $#"