[SOLVED] Bash: recursion = bad?

tuxdev · 05-06-2010, 12:11 PM

Quote:

As someone pointed out in another thread (CTOP) there is no need for the IFS="" when each line is being read into a single variable, in this case $file.

Actually, the IFS is necessary. Try this:

Code:

read -r -d "" line <<< "   foo   "
echo "$foo"
IFS="" read -r -d "" line <<< "   foo   "
echo "$foo"

catkin · 05-06-2010, 12:20 PM

Quote:

Originally Posted by tuxdev

Actually, the IFS is necessary. Try this:

Code:

read -r -d "" line <<< "   foo   "
echo "$line"
IFS="" read -r -d "" line <<< "   foo   "
echo "$line"

Thanks again tuxdev

(and less CTOP and note to self to double check these things).

But I'm puzzled about why in the second case $line has a newline suffixed ... ?

tuxdev · 05-06-2010, 12:27 PM

Quote:

But I'm puzzled about why in the second case $line has a newline suffixed ... ?

The here-string syntax (<<< "") appends a newline to the end. Internally, it actually creates a here-doc and passes that in, like

Code:

IFS="" read -r -d "" line << EOF
   foo   
EOF

(Note that there's three spaces after "foo")

catkin · 05-06-2010, 12:54 PM

Thanks for the clear explanation, tuxdev