Return to pclose.c CVS log

Up to [CSRG BSD Unix] / 43BSD / ucb / ftp

Annotation of 43BSD/ucb/ftp/pclose.c, revision 1.1.1.1

1.1       root        1: /*
                      2:  * Copyright (c) 1980 Regents of the University of California.
                      3:  * All rights reserved.  The Berkeley software License Agreement
                      4:  * specifies the terms and conditions for redistribution.
                      5:  */
                      6: 
                      7: #ifndef lint
                      8: static char sccsid[] = "@(#)pclose.c   1.2 (Berkeley) 3/7/86";
                      9: #endif not lint
                     10: 
                     11: #include <stdio.h>
                     12: #include <signal.h>
                     13: #include <sys/param.h>
                     14: #include <sys/wait.h>
                     15: 
                     16: #define        tst(a,b)        (*mode == 'r'? (b) : (a))
                     17: #define        RDR     0
                     18: #define        WTR     1
                     19: 
                     20: extern char *malloc();
                     21: 
                     22: static int *popen_pid;
                     23: static int nfiles;
                     24: 
                     25: FILE *
                     26: mypopen(cmd,mode)
                     27:        char *cmd;
                     28:        char *mode;
                     29: {
                     30:        int p[2];
                     31:        int myside, hisside, pid;
                     32: 
                     33:        if (nfiles <= 0)
                     34:                nfiles = getdtablesize();
                     35:        if (popen_pid == NULL) {
                     36:                popen_pid = (int *)malloc((unsigned) nfiles * sizeof *popen_pid);
                     37:                if (popen_pid == NULL)
                     38:                        return (NULL);
                     39:                for (pid = 0; pid < nfiles; pid++)
                     40:                        popen_pid[pid] = -1;
                     41:        }
                     42:        if (pipe(p) < 0)
                     43:                return (NULL);
                     44:        myside = tst(p[WTR], p[RDR]);
                     45:        hisside = tst(p[RDR], p[WTR]);
                     46:        if ((pid = vfork()) == 0) {
                     47:                /* myside and hisside reverse roles in child */
                     48:                (void) close(myside);
                     49:                if (hisside != tst(0, 1)) {
                     50:                        (void) dup2(hisside, tst(0, 1));
                     51:                        (void) close(hisside);
                     52:                }
                     53:                execl("/bin/sh", "sh", "-c", cmd, (char *)NULL);
                     54:                _exit(127);
                     55:        }
                     56:        if (pid == -1) {
                     57:                (void) close(myside);
                     58:                (void) close(hisside);
                     59:                return (NULL);
                     60:        }
                     61:        popen_pid[myside] = pid;
                     62:        (void) close(hisside);
                     63:        return (fdopen(myside, mode));
                     64: }
                     65: 
                     66: pabort()
                     67: {
                     68:        extern int mflag;
                     69: 
                     70:        mflag = 0;
                     71: }
                     72: 
                     73: mypclose(ptr)
                     74:        FILE *ptr;
                     75: {
                     76:        int child, pid, omask, pabort(), (*istat)();
                     77:        union wait status;
                     78: 
                     79:        child = popen_pid[fileno(ptr)];
                     80:        popen_pid[fileno(ptr)] = -1;
                     81:        (void) fclose(ptr);
                     82:        if (child == -1)
                     83:                return (-1);
                     84:        istat = signal(SIGINT, pabort);
                     85:        omask = sigblock(sigmask(SIGQUIT)|sigmask(SIGHUP));
                     86:        while ((pid = wait(&status)) != child && pid != -1)
                     87:                ;
                     88:        (void) sigsetmask(omask);
                     89:        (void) signal(SIGINT, istat);
                     90:        return (pid == -1 ? -1 : 0);
                     91: }

This archive runs on limited infrastructure. Preserving old code on modern bandwidth. Automated agents are requested to crawl responsibly.