header containing (PR#13834)

This problem arises on Solaris because apparently Solaris 10 returns the
error "ENOSYS" when you try to make a directory on an automount point
(translates to "unsupported file system operation").

The R mkdir function invokes do_dircreate in platform.c.  The logic in
this function, when the recursive option is set, attempts to mkdir() all
of the antecedent elements of the directory, including directories that
may already exist.  The function is configured to therefore ignore the
"eexist" error returned when do_dircreate attempts to create a directory
that already exists.

The problem thus arises when the directory is, in fact, an automount
point.  Linux returns "eexist" and works.  Solaris returns "enosys" and
thus fails.

I was able to get this to work as expected by updating the check on the
error returned to include enosys as an ignored error:

bash$ diff -C 4 R-2.9.1-orig/src/main/platform.c R-2.9.1/src/main/platform.c

*** R-2.9.1-orig/src/main/platform.c    Sun Mar 22 20:05:03 2009
--- R-2.9.1/src/main/platform.c Thu Aug 20 12:32:15 2009
***************
*** 1960,1968 ****
        p = dir;
        while ((p = Rf_strchr(p+1, '/'))) {
            *p = '\0';
            res = mkdir(dir, mode);
!           if (res && errno != EEXIST) goto end;
            *p = '/';
        }
      }
      res = mkdir(dir, mode);
--- 1960,1968 ----
        p = dir;
        while ((p = Rf_strchr(p+1, '/'))) {
            *p = '\0';
            res = mkdir(dir, mode);
!           if (res && ( errno != EEXIST && errno != ENOSYS )) goto end;
            *p = '/';
        }
      }
      res = mkdir(dir, mode);

I suppose the other way to "fix" this would be to redo the logic to test
for the existance of the directory before attempting to create it.
Probably gets clunky.

Anyway, I'm not sure of the appropriate way to include this as a patch.
I don't know if there's an existing way to "ifdef" this alteration for
solaris only or if the update is generic enough to not cause problems on
other platforms.  I saw a couple other projects implementing recursive
mkdir that just assume enosys isn't fatal and continue on.

Let me know if I can be of further assistance.

Thanks

Michael

---
Michael Gutteridge            Fred Hutchinson CRC
Sr. System Architect          1100 Fairview Ave N
mrg at fhcrc.org                 Mailstop J2-225
                              Seattle, WA 98109