Re: read & leading (and trailing) spaces

[Atom Smasher <atom@xxxxxxxxxxx>]

On Tue, 12 May 2009, Bart Schaefer wrote:

> On May 12,  7:40pm, Atom Smasher wrote:
> }
> } this doesn't work as advertised when the input includes leading and/or
> } trailing spaces:
> }  	read -r foo ; print -r -- "${foo}"
>
> As advertised where?  The doc is silent on the treatment of leading and 
> trailing spaces; under -r, it says only that backslashes aren't special.
>
> (The doc probably *shouldn't* be silent but that's another matter.)
================

my interpretation of "raw" would mean "output is _identical_ to input". 
should i apply a different interpretation to the read builtin?


> I think you'll find that "read" in ksh, bash, etc. also removes leading
> and trailing IFS characters, even with -r.
==================

if all of the other shells jumped off a bridge, would zsh jump too? 
SH_WORD_SPLIT is a good example of all the ~other~ shells being broken and 
zsh doing The Right Thing(tm) by default.


> } i can work around that by setting IFS to either null (IFS='') or setting
> } it to just a newline (IFS='
> } '). should i expect problems (in older or newer versions of zsh) using
> } either of those tricks to make read recognize leading/trailing spaces?
>
> You should not expect problems with that, it's standard IFS behavior.
==================

as long as i can work around it. thanks...


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