Manpage 'man 2 fork' says:
'File locks ... are not inherited.'
This is true for POSIX locks, but not for flock-type locks.
This phrase comes directly from posix fork manpage,
which is not aware of flock-style locks.
Maybe fork manpage should rather say:
... POSIX file locks are not inherited (fcntl(2)).
Flock-style locks are inherited (see flock(2)) ...
?
Yakov