phil@uiucme.UUCP (05/08/84)
#N:uiucme:3100003:000:577 uiucme!phil May 8 11:13:00 1984 I have an HP9000 (please don't laugh). And I'm not sure what's happening in the following - Scenario: My umask is 022. I become super-user. I type in a fortran compile. fc mine.f When the compile is done, I notice that /dev/null has gone from permission 0666 to 0644. This has the side-effect of preventing others from using the fortran or pascal compilers. Why does the permission change? How can I prevent it? I called Hewlett- Packard and they said that I should avoid this situation... Philip Gross uiucdcs!uiucuxc!uiucme!phil U of Illinois, Dept of M&IE
gwyn@brl-vgr.ARPA (Doug Gwyn ) (05/11/84)
Re: HP9000 changes /dev/null mode HP said you should avoid this situation? Hee, hee! Call them back and tell them that the only way you can avoid the situation is to change your computer system vendor!
ajs@hpfcla.UUCP (05/28/84)
This is posted on behalf of the Hewlett Packard Computer Languages Lab.
It is in response to an earlier complaint here about the HP9000 Series
500 FORTRAN compiler. Note that I previously posted a more general
description of the bug in fopen(3s), USG System III version.
Alan Silverstein, Hewlett-Packard Fort Collins Systems Division, Colorado
{ihnp4 | hplabs}!hpfcla!ajs, 303-226-3800 x3053, N 40 31'31" W 105 00'43"
Problem: If a super-user with umask of 022 runs a FORTRAN
compile (on the Series 500) such as "fc myfile.f",
the root removes group and others write permission on
/dev/null. This has the effect of preventing non-
super-users from running the compiler.
Reason: An fopen("/dev/null","w+") call causes umask to be
applied to /dev/null's file permissions. This is
incorrect because /dev/null already exists. Both
the FORTRAN and the Pascal compilers may make calls
of this type to fopen.
Solution: Umask will not be applied to a file that already
exists by an fopen "w+" (create for update) call
under HP-UX version 4.0. Until then, a super-user
with a non-zero umask will usually have to reset the
file permissions ("chmod +rw /dev/null") after a
FORTRAN or a Pascal compile.
From: CLL Technical Support Group