src/common/unix_process.c

#ifndef lint
static const char       RCSid[] = "$Id$";
#endif
/*
 * Routines to communicate with separate process via dual pipes
 * Unix version
 *
 * External symbols declared in standard.h
 */

#include "copyright.h"

#include "rtprocess.h"
#include  "vfork.h"


int
open_process(           /* open communication to separate process */
SUBPROC *pd,
char    *av[]
)
{
        extern char     *getpath(), *getenv();
        char    *compath;
        int     p0[2], p1[2];

        pd->running = 0; /* not yet */
                                        /* find executable */
        compath = getpath(av[0], getenv("PATH"), 1);
        if (compath == 0)
                return(0);
        if (pipe(p0) < 0 || pipe(p1) < 0)
                return(-1);
        if ((pd->pid = vfork()) == 0) {         /* if child */
                close(p0[1]);
                close(p1[0]);
                if (p0[0] != 0) {       /* connect p0 to stdin */
                        dup2(p0[0], 0);
                        close(p0[0]);
                }
                if (p1[1] != 1) {       /* connect p1 to stdout */
                        dup2(p1[1], 1);
                        close(p1[1]);
                }
                execv(compath, av);     /* exec command */
                perror(compath);
                _exit(127);
        }
        if (pd->pid == -1)
                return(-1);
        close(p0[0]);
        close(p1[1]);
        pd->r = p1[0];
        pd->w = p0[1];
        pd->running = 1;
        return(PIPE_BUF);
}


int
close_process(          /* close pipes and wait for process */
SUBPROC *pd
)
{
        int     pid, status;

        close(pd->r);
        close(pd->w);
        pd->running = 0;
        while ((pid = wait(&status)) != -1)
                if (pid == pd->pid)
                        return(status>>8 & 0xff);
        return(-1);             /* ? unknown status */
}


Revision:	3.1
Committed:	Thu Jun 26 00:58:09 2003 UTC (20 years, 10 months ago) by schorsch
Content type:	text/plain
Branch:	MAIN
Log Message:	Abstracted process and path handling for Windows. Renamed FLOAT to RREAL because of conflict on Windows. Added conditional compiles for some signal handlers.
#	User	Rev	Content
1	schorsch	3.1	#ifndef lint
2			static const char RCSid[] = "$Id$";
3			#endif
4			/*
5			* Routines to communicate with separate process via dual pipes
6			* Unix version
7			*
8			* External symbols declared in standard.h
9			*/
10
11			#include "copyright.h"
12
13			#include "rtprocess.h"
14			#include "vfork.h"
15
16
17			int
18			open_process( /* open communication to separate process */
19			SUBPROC *pd,
20			char *av[]
21			)
22			{
23			extern char getpath(), getenv();
24			char *compath;
25			int p0[2], p1[2];
26
27			pd->running = 0; /* not yet */
28			/* find executable */
29			compath = getpath(av[0], getenv("PATH"), 1);
30			if (compath == 0)
31			return(0);
32			if (pipe(p0) < 0 \|\| pipe(p1) < 0)
33			return(-1);
34			if ((pd->pid = vfork()) == 0) { /* if child */
35			close(p0[1]);
36			close(p1[0]);
37			if (p0[0] != 0) { /* connect p0 to stdin */
38			dup2(p0[0], 0);
39			close(p0[0]);
40			}
41			if (p1[1] != 1) { /* connect p1 to stdout */
42			dup2(p1[1], 1);
43			close(p1[1]);
44			}
45			execv(compath, av); /* exec command */
46			perror(compath);
47			_exit(127);
48			}
49			if (pd->pid == -1)
50			return(-1);
51			close(p0[0]);
52			close(p1[1]);
53			pd->r = p1[0];
54			pd->w = p0[1];
55			pd->running = 1;
56			return(PIPE_BUF);
57			}
58
59
60
61			int
62			close_process( /* close pipes and wait for process */
63			SUBPROC *pd
64			)
65			{
66			int pid, status;
67
68			close(pd->r);
69			close(pd->w);
70			pd->running = 0;
71			while ((pid = wait(&status)) != -1)
72			if (pid == pd->pid)
73			return(status>>8 & 0xff);
74			return(-1); /* ? unknown status */
75			}
76
77