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/*
* Copyright (c) 2010, Oracle America, Inc.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are
* met:
*
* * Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* * Redistributions in binary form must reproduce the above
* copyright notice, this list of conditions and the following
* disclaimer in the documentation and/or other materials
* provided with the distribution.
* * Neither the name of the "Oracle America, Inc." nor the names of its
* contributors may be used to endorse or promote products derived
* from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
* COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
* INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE
* GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
* WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
* NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
/*
* Open two pipes to a child process, one for reading, one for writing.
* The pipes are accessed by FILE pointers. This is NOT a public
* interface, but for internal use only!
*/
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <string.h>
#include <rpc/rpc.h>
#include <rpc/clnt.h>
#include <libio/iolibio.h>
#define fflush(s) _IO_fflush (s)
#define __fdopen(fd,m) _IO_fdopen (fd,m)
/*
* returns pid, or -1 for failure
*/
int
_openchild (const char *command, FILE ** fto, FILE ** ffrom)
{
int i;
int pid;
int pdto[2];
int pdfrom[2];
if (__pipe (pdto) < 0)
goto error1;
if (__pipe (pdfrom) < 0)
goto error2;
switch (pid = __fork ())
{
case -1:
goto error3;
case 0:
/*
* child: read from pdto[0], write into pdfrom[1]
*/
__close (0);
__dup (pdto[0]);
__close (1);
__dup (pdfrom[1]);
fflush (stderr);
for (i = _rpc_dtablesize () - 1; i >= 3; i--)
__close (i);
fflush (stderr);
execlp (command, command, NULL);
perror ("exec");
_exit (~0);
default:
/*
* parent: write into pdto[1], read from pdfrom[0]
*/
*fto = __fdopen (pdto[1], "w");
__close (pdto[0]);
*ffrom = __fdopen (pdfrom[0], "r");
__close (pdfrom[1]);
break;
}
return pid;
/*
* error cleanup and return
*/
error3:
__close (pdfrom[0]);
__close (pdfrom[1]);
error2:
__close (pdto[0]);
__close (pdto[1]);
error1:
return -1;
}
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