[PATCH] posix: execvpe: skip $PATH components that are too long

[Paul Eggert]

On 2025-11-08 09:09, Bruno Haible wrote:
> The kernel will return ENAMETOOLONG for attempts
> to access D1/F. However, this does *not* mean that F does
> not exist in F1. Therefore, it does *not* mean that D2/F
> should be picked and executed.

I'm not quite seeing that. POSIX says that the search continues "until 
an executable file with appropriate execution permissions is found"[1] 
so it boils down to what is meant by "found". My interpretation is that 
ENAMETOOLONG means such a file is not "found" there, so the search 
should continue.

For what it's worth, FreeBSD execvpe[2] treats ENAMETOOLONG the same way 
as the proposed patch.

FreeBSD puts ELOOP into the same category as ENOENT/ENAMETOOLONG/etc., 
and it would make sense to add ELOOP while we're in the neighborhood. 
That is, a symlink loop should not prevent execvpe from looking later in 
PATH, as such a loop means the file was not "found" at the current spot.

[1]: 
https://pubs.opengroup.org/onlinepubs/9799919799/basedefs/V1_chap08.html#tag_08_03
[2]: 
https://github.com/freebsd/freebsd-src/blob/main/lib/libc/gen/exec.c#L159