4.3BSD - /usr/src/usr.bin/learn/selsub.c

   1: #ifndef lint
   2: static char sccsid[] = "@(#)selsub.c	4.3	(Berkeley)	5/15/86";
   3: #endif not lint
   4: 
   5: #include "stdio.h"
   6: #include "sys/types.h"
   7: #include "sys/stat.h"
   8: #include "lrnref.h"
   9: 
  10: char learnrc[100];
  11: 
  12: selsub(argc,argv)
  13: char *argv[];
  14: {
  15:     char ans1[100];
  16:     static char ans2[40];
  17:     static char dirname[40];
  18:     static char subname[40];
  19:     FILE *fp;
  20:     char *getenv();
  21:     char *home;
  22: 
  23:     if (argc > 1 && argv[1][0] == '-') {
  24:         direct = argv[1]+1;
  25:         argc--;
  26:         argv++;
  27:     }
  28:     if (chdir(direct) != 0) {
  29:         perror(direct);
  30:         fprintf(stderr, "Selsub:  couldn't cd to non-standard directory\n");
  31:         exit(1);
  32:     }
  33:     sname = argc > 1 ? argv[1] : 0;
  34:     if (argc > 2) {
  35:         strcpy (level=ans2, argv[2]);
  36:         if (strcmp(level, "-") == 0)    /* no lesson name is - */
  37:             ask = 1;
  38:         else if (strcmp(level, "0") == 0)
  39:             level = 0;
  40:         else
  41:             again = 1;  /* treat as if "again" lesson */
  42:     }
  43:     else
  44:         level = 0;
  45:     if (argc > 3 )
  46:         speed = atoi(argv[3]);
  47:     if ((home = getenv("HOME")) != NULL) {
  48:         sprintf(learnrc, "%s/.learnrc", home);
  49:         if ((fp=fopen(learnrc, "r")) != NULL) {
  50:             char xsub[40], xlev[40]; int xsp;
  51:             fscanf(fp, "%s %s %d", xsub, xlev, &xsp);
  52:             fclose(fp);
  53:             if (*xsub && *xlev && xsp >= 0  /* all read OK */
  54:                 && (argc == 2 && strcmp(sname, xsub) == 0
  55:                   || argc <= 1)) {
  56:                 strcpy(sname = subname, xsub);
  57:                 strcpy(level = ans2, xlev);
  58:                 speed = xsp;
  59:                 again = 1;
  60:     printf("[ Taking up where you left off last time:  learn %s %s.\n",
  61:         sname, level);
  62:     printf("%s\n  \"rm $HOME/.learnrc\", and re-enter with \"learn %s\". ]\n",
  63:         "  To start this sequence over leave learn by typing \"bye\", then",
  64:         sname);
  65:             }
  66:         }
  67:     }
  68:     if (!sname) {
  69:         printf("These are the available courses -\n");
  70:         list("Linfo");
  71:         printf("If you want more information about the courses,\n");
  72:         printf("or if you have never used 'learn' before,\n");
  73:         printf("press RETURN; otherwise type the name of\n");
  74:         printf("the course you want, followed by RETURN.\n");
  75:         fflush(stdout);
  76:         gets(sname=subname);
  77:         if (sname[0] == '\0') {
  78:             list("Xinfo");
  79:             do {
  80:                 printf("\nWhich subject?  ");
  81:                 fflush(stdout);
  82:                 gets(sname=subname);
  83:             } while (sname[0] == '\0');
  84:         }
  85:     }
  86:     chknam(sname);
  87:     total = cntlessons(sname);
  88:     if (!level) {
  89:         printf("If you were in the middle of this subject\n");
  90:         printf("and want to start where you left off, type\n");
  91:         printf("the last lesson number the computer printed.\n");
  92:         printf("If you don't know the number, type in a word\n");
  93:         printf("you think might appear in the lesson you want,\n");
  94:         printf("and I will look for the first lesson containing it.\n");
  95:         printf("To start at the beginning, just hit RETURN.\n");
  96:         fflush(stdout);
  97:         gets(ans2);
  98:         if (ans2[0]==0)
  99:             strcpy(ans2,"0");
 100:         else
 101:             again = 1;
 102:         level=ans2;
 103:         getlesson();
 104:     }
 105: 
 106:     /* make new directory for user to play in */
 107:     if (chdir("/tmp") != 0) {
 108:         perror("/tmp");
 109:         fprintf(stderr, "Selsub:  couldn't cd to public directory\n");
 110:         exit(1);
 111:     }
 112:     sprintf(dir=dirname, "pl%da", getpid());
 113:     sprintf(ans1, "mkdir %s", dir);
 114:     system(ans1);
 115:     if (chdir(dir) < 0) {
 116:         perror(dir);
 117:         fprintf(stderr, "Selsub:  couldn't make play directory with %s.\nBye.\n", ans1);
 118:         exit(1);
 119:     }
 120:     /* after this point, we have a working directory. */
 121:     /* have to call wrapup to clean up */
 122:     if (access(sprintf(ans1, "%s/%s/Init", direct, sname), 04)==0)
 123:         if (system(sprintf(ans1, "%s/%s/Init %s", direct, sname, level)) != 0) {
 124:             printf("Leaving learn.\n");
 125:             wrapup(1);
 126:         }
 127: }
 128: 
 129: chknam(name)
 130: char *name;
 131: {
 132:     if (access(name, 05) < 0) {
 133:         printf("Sorry, there is no subject or lesson named %s.\nBye.\n", name);
 134:         exit(1);
 135:     }
 136: }
 137: 
 138: #ifndef DIR
 139: #include <sys/dir.h>
 140: #endif
 141: 
 142: cntlessons(sname)   /* return number of entries in lesson directory; */
 143: char *sname;        /* approximate at best since I don't count L0, Init */
 144: {           /* and lessons skipped by good students */
 145: #if BSD4_2
 146:     struct direct dbuf;
 147:     register struct direct *ep = &dbuf; /* directory entry pointer */
 148:     int n = 0;
 149:     DIR *dp;
 150: 
 151:     if ((dp = opendir(sname)) == NULL) {
 152:         perror(sname);
 153:         wrapup(1);
 154:     }
 155:     for (ep = readdir(dp); ep != NULL; ep = readdir(dp)) {
 156:         if (ep->d_ino != 0)
 157:             n++;
 158:     }
 159:     closedir(dp);
 160:     return n - 2;               /* minus . and .. */
 161: #else
 162:     struct stat statbuf;
 163: 
 164:     stat(sname, &statbuf);
 165:     return statbuf.st_size / 16 - 2;
 166: #endif
 167: }

Defined functions

Defined variables