with a NULL argument.
* src/useradd.c: Replace PATH_MAX by a fixed constant. The buffer
was not meant as a storage for a path.
* src/useradd.c, src/newusers.c, src/chpasswd.c: Better detection
of fgets errors. Lines shall end with a \n, unless we reached the
end of file.
* libmisc/copydir.c: Avoid PATH_MAX. Support file paths with any
length. Added readlink_malloc().