ACCESS(2) sometimes NOT useful - (nf)
edwards at uiucuxc.UUCP
edwards at uiucuxc.UUCP
Fri Sep 23 13:45:03 AEST 1983
#N:uiucuxc:5500067:000:849
uiucuxc!edwards Sep 6 22:00:00 1983
The 4.1bsd manual states that access(2) uses a program's real
id's to determine access permissions on files/paths, and that this
is useful to set-UID programs.
Well, It really depends on what you're checking. If a set-UID
program wants to do things to privileged areas, then access(2) is NOT
useful to those set-UID programs.
For example: If your set-UID program wants to see if a directory
exists in a privileged area "access to a set-UIDed
program or user only," then you can't use access(2)
because the real [ug]id of the process wouldn't have
access anyway (the purpose for making it Set-UID.)
Suggestion: eaccess(2) or equivalent to check for effective id's.
What do you think about it? Nasty comments >> /dev/null
Alan Edwards
University of Illinois @ Urbana-Champaign
(...pur-ee!uiucdcs!uiucuxc!edwards)
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