[Nix-dev] maybe to silent WARNING when setuid program doesn't exist?

[Marc Weber]

Activating the configuration...
WARNING: No executable named `ssmtp' was found
WARNING: but `ssmtp' was specified as a setuid program.
WARNING: No executable named `sendmail' was found
WARNING: but `sendmail' was specified as a setuid program.
[....]

[root at mail:/home/marc]# ssmtp 
ssmtp: /nix/store/iqvl6cbgj1kzdvn8fd0i0ql2d9kxwzd2-setuid-wrapper.c:66:
main: Assertion `len > 0' failed.
Aborted

[root at mail:/home/marc]# sendmail 
sendmail:
/nix/store/iqvl6cbgj1kzdvn8fd0i0ql2d9kxwzd2-setuid-wrapper.c:66: main:
Assertion `len > 0' failed.
Aborted


The resulting error is missleading. What about adding a comment within
the c source file what has gone wrong or better:
print a nice error message such as:
        "Ouups ? Something has gone wrong. Propably I've been compiled when app
        xx hasn't been in path, add it to extraPackages and try again"

Or maybe make the WARNING fatal and put the at the beginning of
"activate-configuration.sh"? I'd prefer this last solution

Sincerly
Marc Weber