Array of structures and using variables of pointer to functions

Question

Basically I want to input a string of text and if it matches with the string on the structure (*cmd_name), the program will then call and execute the function that corresponds to it. Here's my attempt:

#include <stdio.h>
#include <stdlib.h>
#include <string.h>

void new_cmd()
 {
     printf("You entered new_cmd function!");
 }
void close_cmd()
 {
     printf("You entered close_cmd function!");
 }
 void open_cmd()
 {
     printf("You entered open_cmd function!");
 }
 void close_all_cmd()
 {
     printf("You entered the close_all_cmd function!");
 }

struct{
    char *cmd_name;
    void (*cmd_pointer)(void);              //variable of a pointer to a function
     }file_cmd[]= {  {"new",      new_cmd},
                  {"open",    open_cmd},
                  {"close",    close_cmd},
                  {"close all",   close_all_cmd}};


int main()
{
   int i;
   char my_string[15];

   scanf("%s",my_string);
   for(i=0; i<4;i++)
      if(file_cmd[i].cmd_name == my_string)       //matching the string
       {
           file_cmd[i].cmd_pointer();            //possible mistake here, trying to open the function
           break;
       }  

    return 0; 
}

Whenever I test this and write on the command line "new" or any string, the program doesn't execute at all and exits.

`==` can't compare string, only addresses. Use `strcmp`. Plenty of similar question on SO, search first. — Jean-Baptiste Yunès, Aug 31 '16 at 06:40
Possible duplicate of [How do I properly compare strings in C?](http://stackoverflow.com/questions/8004237/how-do-i-properly-compare-strings-in-c) — Jean-Baptiste Yunès, Aug 31 '16 at 06:41

score 2 · Answer 1 · answered Aug 31 '16 at 06:29

You can not compare strings using ==, you have to use strcmp().

That said, scanf("%s",my_string); should better be scanf("%14s",my_string); to avoid buffer overlow by longer-than-expected input. Also, you should always check the return value of scanf() to ensure success.

Array of structures and using variables of pointer to functions

1 Answers1