getInt

gistfile1.txt

int GetInt(void)
{
    // try to get an int from user
    while (true)
    {
        // get line of text, returning INT_MAX on failure
        string line = GetString();
        if (line == NULL)
        {
            return INT_MAX;
        }

        // return an int if only an int (possibly with
        // leading and/or trailing whitespace) was provided
        int n; char c;
        if (sscanf(line, " %d %c", &n, &c) == 1)
        {
            free(line);
            return n;
        }
        else
        {
            free(line);
            printf("Retry: ");
        }
    }
}