On 4/11/2017 3:02 PM, Christian Franke wrote: > cyg Simple wrote: >> >> -i, --ignore-environment start with an empty environment >> >> A relative use of the executable will not be found if the environment is >> empty. > > Not necessarily (see Linux, *BSD, ...). POSIX says this is > "implementation-defined" - under the assumption that 'env' uses execvp() > which is the case for the GNU coreutils version. >
> POSIX says this is "implementation-defined" Which means it is undefined by POSIX. Also one could argue that --ignore-environment also means any default ones within an API set. > >>> Interestingly the approach in newlib/libc/posix/execvp.c differs from >>> Cygwin and others: >>> execvp() with PATH unset calls execv(). This has the same effect as >>> execvp() with PATH set to current directory only. >>> >> Why do you assume that this is an issue with execvp? > > I never did (otherwise this would be a thread on cygwin-patches list). > > The above only means that it is IMO interesting that the Cygwin source > package contains two implementations of execvp() which handle the unset > PATH situation differently. > Sure, but it is implemented correctly based on POSIX. ;) > >> The user should >> not expect that an undefined behavior behaves the same way on other >> systems. > > Of course. But even then it is a reasonable question which possible > alternative should be implemented by Cygwin. Cygwin homepage says "Get > that Linux feeling, ...". So "implementation-defined" behavior should > possibly be close to Linux :-) > Even so not all "Linux feeling" can be implemented. But I agree it should be as close as possible. But I don't believe that env --ignore-environment should be using execvp and should be using execv instead. That is for the upstream coreutils team to decide though. -- cyg Simple -- Problem reports: http://cygwin.com/problems.html FAQ: http://cygwin.com/faq/ Documentation: http://cygwin.com/docs.html Unsubscribe info: http://cygwin.com/ml/#unsubscribe-simple
