Thread: How do I pass options at the prompt.

First the code

Code:

[cdalten@localhost YAPP]$ more main.c
#include <stdio.h>
#include <stdlib.h>

int 
main(int argc, char *argv[])
{

  conference(&argc, &argv);

  /*cleanup();*/
  exit(EXIT_SUCCESS);
}
[cdalten@localhost YAPP]$

Code:

[cdalten@localhost YAPP]$ more driver.c
#include <stdio.h>
#include <stdlib.h>
#include <string.h>

static char buf[BUFSIZ];

int strip_line(char line[]) {
  int n;

  for (n = strlen(line)-1; n >= 0; n--)
    if (line[n] != ' ' && line[n] != '\t')
      break;
  line[n+1] = '\0';
  return n;
}

void conference_prompt(void) {
  fputs("Type Help for more information\n", stdout);

  do {
    strip_line(buf);
    fputs("OK:", stdout);
    fflush(stdout);
  } while (fgets(buf, BUFSIZ, stdin) != NULL); 
}


void conference(int *argc, char *argv[]) {
  if (*argc == 1) {
    conference_prompt();
  }
}

[cdalten@localhost YAPP]$

[cdalten@localhost YAPP]$ gcc main.c driver.c -o yapp
[cdalten@localhost YAPP]$ ./yapp
Type Help for more information
OK:

What I want to do is for a user to get a help menu when they type 'h' or 'help' at the 'OK:' prompt. I looked at getopt() but that only seems to work with command line args. And the switch statement doesn't seem to want to work when it see something like 'help'. Ideas?

You do it the same way for any function.

Code:

int foo(int argc, char **argv)
{
        printf("argc = %i, argv[0] = %s\n", argc, argv[0]);
        return 0;
}
int main(int argc, char **argv)
{
        return foo(argc, argv);
}

But I don't want 'h' passed at the command line. Ie, I don't want

./yapp h

I just want 'h' passed a the 'OK:' prompt.

Ah, I see. I gotta bad habit about not reading the whole sentence. . .

Code:

char *cmds[] = { "H", "HELP", "ETC", "\0" };
int match(const char *which)
{
        int i;
        for (i = 0; cmds[i][0] != '\0'; i++){
                if (!strcmp(cmds[i], upcase(which)){
                        break;
                }
        }
        if (cmds[i][0] != '\0'){
                return -1;
        }
        return i;
}

You'll have to write upcase.

[edit] switch(match(userinput)){[/edit]

You might want to read the manpage for getopt as that will do you option handling for you. Saves reinventing the wheel.

Oops, I misread your post >_<