Re: pkill

[Alfred M\. Szmidt]

   Remember, POSIX requires kill(1) to be a shell builtin, because it
   must support job syntax ("kill %1", for example), which cannot be
   done with normal POSIX child process semantics.

In that case, one can make the builtin kill a wrapper, that parses the
command line, and if it see %1 it replaces it with the process job pid
and passes that to the real kill, or the builtin kill if no system
kill utiltiy exists.

Just cause POSIX says something, doesn't mean that it is right.