Commit | Line | Data |
---|---|---|
e343f97a KS |
1 | #include <stdio.h> |
2 | #include <signal.h> | |
ea394d88 | 3 | #include <errno.h> |
e343f97a KS |
4 | #define tst(a,b) (*mode == 'r'? (b) : (a)) |
5 | #define RDR 0 | |
6 | #define WTR 1 | |
7 | static int popen_pid[20]; | |
4bc721c3 | 8 | static char *sccsid = "@(#)popen.c 1.6 %G%"; |
ea394d88 | 9 | |
4bc721c3 SL |
10 | #ifdef VMUNIX |
11 | #define mask(s) (1<<((s)-1)) | |
12 | #else | |
13 | #define vfork fork | |
14 | #endif VMUNIX | |
d3c349a9 CS |
15 | #ifndef SIGRETRO |
16 | #define sigchild() | |
17 | #endif | |
e343f97a KS |
18 | |
19 | FILE * | |
20 | popen(cmd,mode) | |
21 | char *cmd; | |
22 | char *mode; | |
23 | { | |
24 | int p[2]; | |
25 | register myside, hisside, pid; | |
26 | ||
27 | if(pipe(p) < 0) | |
28 | return NULL; | |
29 | myside = tst(p[WTR], p[RDR]); | |
30 | hisside = tst(p[RDR], p[WTR]); | |
31 | if((pid = vfork()) == 0) { | |
32 | /* myside and hisside reverse roles in child */ | |
cb9e16fc | 33 | sigchild(); |
e343f97a KS |
34 | close(myside); |
35 | dup2(hisside, tst(0, 1)); | |
36 | close(hisside); | |
37 | execl("/bin/csh", "sh", "-c", cmd, 0); | |
38 | _exit(1); | |
39 | } | |
40 | if(pid == -1) | |
41 | return NULL; | |
42 | popen_pid[myside] = pid; | |
43 | close(hisside); | |
44 | return(fdopen(myside, mode)); | |
45 | } | |
46 | ||
47 | pclose(ptr) | |
48 | FILE *ptr; | |
49 | { | |
39c234be | 50 | register f, r; |
4bc721c3 | 51 | int status, omask; |
ea394d88 | 52 | extern int errno; |
e343f97a KS |
53 | |
54 | f = fileno(ptr); | |
55 | fclose(ptr); | |
ea394d88 | 56 | # ifdef VMUNIX |
4bc721c3 | 57 | omask = sigblock(mask(SIGINT)|mask(SIGQUIT)|mask(SIGHUP)); |
ea394d88 KS |
58 | # endif VMUNIX |
59 | while((r = wait(&status)) != popen_pid[f] && r != -1 && errno != EINTR) | |
e343f97a KS |
60 | ; |
61 | if(r == -1) | |
62 | status = -1; | |
ea394d88 | 63 | # ifdef VMUNIX |
4bc721c3 | 64 | sigsetmask(omask); |
ea394d88 | 65 | # endif VMUNIX |
e343f97a KS |
66 | return(status); |
67 | } |