Shell Programming and Scripting

... provided IFS is set to $'\n'

Expanding on what Scrutinizer said... As already explained in this thread, this only works if IFS is set to the <newline> character.

With a default setting of IFS (IFS=$' \t\n'), that command would produce something more like:

Code:

List of files total
List of filesl 12
List of files -rw-rw-r--.
List of files 1
List of files aia
List of files aia
List of files 148
List of files Jun
List of files 7
List of files 19:49
List of files index.html
... ... ...

And, you get the same results with:

Code:

IFS=$'\n' printf "List of files %s\n" $(ls -ltr)

because that only sets IFS in the environment for the invocation of printf; not for the evaluation of the results of the command substitution done in the current shell execution environment when preparing arguments to be passed to printf.

It puzzles me that since it was "already explained in this thread" you have to repeat again what it was explained.

Can I choose to let whoever comes across the thread to make that determination of understanding? May I post, without arousing your urge to comment back in a rectifying tone?

I apologize if I have offended you.

I believe The UNIX & Linux Forums is a place where inexperienced users can learn how to effectively to get their jobs done using the tools available on UNIX systems, Linux systems, and other systems that provide UNIX system or Linux system utilities.

When posts are added to a discussion suggesting that the submitter use something that won't work 99% of the time, the other people reading the thread can choose to ignore it and assume the newbies will eventually figure out that the suggestions found here are not moderated, may be more confusing than helpful, and it is up to them to determine the usefulness of the suggestions. Or an interested reader might try to explain why a given suggestion won't (at least in many circumstances) work so newbies can learn more quickly what works, what doesn't work, and why.

Sorry, I apologize, as well.

Thanks All,it's working fine i use IFS option

Instead of saving and restoring IFS, one can set IFS in a sub-shell:

Code:

(
IFS='
'
cnt=0
for i in $(ls -ltr)
do
  cnt=$((cnt+1))
  echo "line ${cnt}: $i"
done
echo "total: $cnt lines"
)
# won't work in the main shell: echo "total: $cnt lines"

Of course any variable that is set in the sub-shell will not be in the main shell.
Also a while loop runs in a sub-shell (at least if fed from a pipe):

Code:

cnt=0
ls -ltr |
while read i
do
  cnt=$((cnt+1))
  echo "line ${cnt}: $i"
done
# won't work in the main shell: echo "total: $cnt lines"