Question

Ah, thanks! Makes sense. Just made command of size MAX_COMMAND_LENGTH + 1.

I am trying to to use fscanf to read the same file 2 different times in a loop but I am getting a seg fault. The idea is that the file will be formatted so that it has a command at the beginning of each line, followed by arguments for the command.

  char* command;  //Changed to char command[MAX_COMMAND_LENGTH + 1]

  while(fscanf(file, "%s", command) == 1)
  {
    if (strcmp("CMD1", command) == 0)
    {    
      int index, exp, coeff;
      fscanf(file, "%d %d %d", &index, &exp, &coeff);
    }
    else if (strcmp("CMD2", command) == 0)
    {
      int num;
      fscanf(file, "%d", &num);
    }
}

Answer 1

You need to allocate memory for command. For example:

command = (char *)malloc(1024 * sizeof(char));

will allocate enough memory for 1024 characters.

Remember to free(command) when you’re finished with it.