Read space as input in shell script

Question

How can I give space " " as input in shell script ?

Ex :

echo " Enter date for grep... Ex: Oct  6 [***Double space is important for single date***] (or) Oct 12 "
read mdate 
echo $mdate

I get the output as Oct 6 but I want Oct 6.

score 11 · Accepted Answer · edited Apr 13 '17 at 12:37

11

You already have Oct 6 in $mdate, your problem is that you're expanding it when printing. Always use double quotes around variable substitutions. Additionally, to retain leading and trailing whitespace (those are stripped by read), set IFS to the empty string.

IFS= read -r mdate
echo "$mdate"

The -r (raw) option to read tells it not to treat backslashes specially, which is what you want most of the time (but it's not the problem here).

edited Apr 13 '17 at 12:37

Community

1

answered Oct 14 '10 at 07:16

Gilles 'SO- stop being evil'

829,060

can we also ensure the beginning and ending spaces are not dropped? read toto ; echo "$toto" : when i enter ______this____ (_ are spaces) it outputs this (I believe this is not something done by read, but by the shell's line policy? how to change it? stty raw before the read, or something?) – Olivier Dulac Oct 09 '14 at 07:44
1

@OlivierDulac Yes, this needed IFS=. This is about the shell, it has nothing to do with terminal settings. – Gilles 'SO- stop being evil' Oct 09 '14 at 07:49
I found it : OLDIFS="$IFS" ; IFS="" read toto ; echo "__${toto}__" ; IFS="${OLDIFS}" – Olivier Dulac Oct 09 '14 at 07:50
oh; thanks for that quick reply, that I only saw when I typed my 2nd comment ^^ +1, sir! – Olivier Dulac Oct 09 '14 at 07:51
1

@OlivierDulac No need for anything so complicated. Just set IFS for the duration of the read call. – Gilles 'SO- stop being evil' Oct 09 '14 at 07:51
I need coffee... indeed: IFS='' read toto will change IFS just for the duration of the call to read ... (I know this, usually...) – Olivier Dulac Oct 09 '14 at 07:53

Read space as input in shell script

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