Hugs, Mac OS X 10.1.5, and pathnames

[Hamilton Richards]

I originally wrote:

>  > In OS X, pathnames have two distinct syntaxes. The GUI uses the pre-X
>>  syntax, in which a pathname begins with a volume name and the
>>  separator is `:', as in
>>
>>	Macintosh HD:Users:ham:Documents:whatever.hs
>>
>>  In the Darwin (i.e., unix) command-line "underworld", a pathname
>>  begins with /Volumes, spaces are escaped with `\', and the separator
>>  is `/', as in
>>
>>	/Volumes/Macintosh\ HD/Users/ham/Documents/whatever.hs
>>
>>  When you drag a file icon onto the command line, Terminal does the
>>  right thing-- it converts the pathname from the GUI syntax to the
>>  Darwin syntax, and utilities such as more work just as they should.
>>
>>  Hugs, however, doesn't do so well. For example,
>>
>>      Prelude> :l /Volumes/Macintosh\ HD/Users/ham/Documents/whatever.hs
>>      Reading file "/Volumes/Macintosh\":
>>      ERROR "/Volumes/Macintosh\" - Unable to open file "/Volumes/Macintosh\"
>>
>>  Quoting the pathname changes the problem, but doesn't cure it:
>>
>>      Prelude> :l "/Volumes/Macintosh\ HD/Users/ham/Documents/whatever.hs"
>>      ERROR - Missing `\' terminating string literal gap
>>
>>  Apparently what's confusing Hugs is the `\', because removing it
>>  cures the problem:
>>
>>      Prelude> :l "/Volumes/Macintosh HD/Users/ham/Documents/whatever.hs"
>>      Reading file "/Volumes/Macintosh HD/Users/ham/Documents/whatever.hs":
>>
>>  Is this problem unavoidable, or is it just an oversight?

At 6:02 AM +0100 9/1/02, Glynn Clements replied:
>
>The backslash isn't actually part of the pathname; it's added to
>prevent the shell from splitting the pathname into multiple arguments.
>The shell converts the backslash-space sequence into a space.
>
>The same issue arises in other languages; e.g. in C,
>
>	const char *name = "/Volumes/Macintosh 
>HD/Users/ham/Documents/whatever.hs";
>	FILE *fp = fopen(name, "r");
>
>would work, but including the backslash would break it.
>
>--
>Glynn Clements <glynn.clements@virgin.net>
>


I do actually understand that the backslash isn't part of the 
pathname. My question is whether there's any reason Hugs couldn't 
treat backslashes in its command line as C shells do.

I suspect it's just something no one thought about, because spaces 
are uncommon in unix file names.

--Ham

-- 
------------------------------------------------------------------
Hamilton Richards                Department of Computer Sciences
Senior Lecturer                  The University of Texas at Austin
512-471-9525                     1 University Station C0500
Taylor Hall 5.138                Austin, Texas 78712-1188
ham@cs.utexas.edu                hrichrds@swbell.net
------------------------------------------------------------------