#include "defs" #include dosys(comstring,nohalt) register char *comstring; int nohalt; { register int status; if(metas(comstring)) status = doshell(comstring,nohalt); else status = doexec(comstring); return(status); } metas(s) /* Are there are any Shell meta-characters? */ register char *s; { register char c; while( (funny[c = *s++] & META) == 0 ) ; return( c ); } doshell(comstring,nohalt) char *comstring; int nohalt; { if((waitpid = fork()) == 0) { enbint(SIG_DFL); doclose(); execl(SHELLCOM, "sh", (nohalt ? "-c" : "-ce"), comstring, 0); fatal("Couldn't load Shell"); } return( await() ); } await() { int intrupt(); int status; register int pid; enbint(SIG_IGN); while( (pid = wait(&status)) != waitpid) if(pid == -1) fatal("bad wait code"); waitpid = 0; enbint(intrupt); return(status); } doclose() /* Close open directory files before exec'ing */ { register struct opendir *od; for (od = firstod; od; od = od->nxtopendir) if (od->dirfc != NULL) fclose(od->dirfc); } doexec(str) register char *str; { register char *t; char *argv[200]; register char **p; while( *str==' ' || *str=='\t' ) ++str; if( *str == '\0' ) return(-1); /* no command */ p = argv; for(t = str ; *t ; ) { *p++ = t; while(*t!=' ' && *t!='\t' && *t!='\0') ++t; if(*t) for( *t++ = '\0' ; *t==' ' || *t=='\t' ; ++t) ; } *p = NULL; if((waitpid = fork()) == 0) { enbint(SIG_DFL); doclose(); enbint(intrupt); execvp(str, argv); fatal1("Cannot load %s",str); } return( await() ); } #include #include #include touch(force, name) int force; char *name; { struct stat stbuff; char junk[1]; int fd; if( stat(name,&stbuff) < 0) if(force) goto create; else { fprintf(stderr, "touch: file %s does not exist.\n", name); return; } if(stbuff.st_size == 0) goto create; if( (fd = open(name, 2)) < 0) goto bad; if( read(fd, junk, 1) < 1) { close(fd); goto bad; } lseek(fd, 0L, 0); if( write(fd, junk, 1) < 1 ) { close(fd); goto bad; } close(fd); return; bad: fprintf(stderr, "Cannot touch %s\n", name); return; create: if( (fd = creat(name, 0666)) < 0) goto bad; close(fd); }