Files
mercury/extras/posix/posix.pipe.m
Julien Fischer 9751360ca4 Style and formatting fixes for the POSIX binding.
extras/posix/*.m:
    As above.
2019-03-22 10:53:31 +00:00

58 lines
1.8 KiB
Mathematica

%-----------------------------------------------------------------------------%
% vim: ft=mercury ts=4 sw=4 et
%-----------------------------------------------------------------------------%
% Copyright (C) 2001, 2007 The University of Melbourne.
% Copyright (C) 2018-2019 The Mercury team.
% This file is distributed under the terms specified in COPYING.LIB.
%-----------------------------------------------------------------------------%
%
% Module: posix.pipe.
% Main author: Michael Day <miked@lendtech.com.au>
%
%-----------------------------------------------------------------------------%
:- module posix.pipe.
:- interface.
%-----------------------------------------------------------------------------%
:- pred pipe(posix.result({fd, fd})::out, io::di, io::uo) is det.
%-----------------------------------------------------------------------------%
%-----------------------------------------------------------------------------%
:- implementation.
:- import_module int.
:- pragma foreign_decl("C", "
#include <sys/types.h>
#include <unistd.h>
").
%-----------------------------------------------------------------------------%
pipe(Result, !IO) :-
pipe0(Reading, Writing, Res, !IO),
( if Res \= 0 then
errno(Err, !IO),
Result = error(Err)
else
Result = ok({Reading, Writing})
).
:- pred pipe0(fd::out, fd::out, int::out, io::di, io::uo) is det.
:- pragma foreign_proc("C",
pipe0(R::out, W::out, Res::out, _IO0::di, _IO::uo),
[promise_pure, will_not_call_mercury, tabled_for_io],
"
int filedes[2];
Res = pipe(filedes);
R = filedes[0];
W = filedes[1];
").
%-----------------------------------------------------------------------------%
:- end_module posix.pipe.
%-----------------------------------------------------------------------------%