C: strtok value gives back null

Question

I am trying to parse a HTTP request header. I need to pickup the first line:

GET / HTTP/1.1

However, the output for the code below is:

Method: (null)
Filename: (null)
Version: (null)
Client hostname: (null)

Why?

Code:

    char *token;
    const char delimiter[2] = " ";
    token = strtok(NULL, delimiter);

Answer 1

The delimiter has to be " \r\n", otherwise some parts will be concatenated

    // Parse the request                                                                                  
    char *token;
    const char delimiter[6] = " \r\n";

    token = strtok(buffer, delimiter);
    method = token;
    printf("Method: %s\n", method);

    token = strtok(NULL, delimiter);
    filename = token;
    printf("Filename: %s\n", filename);

    token = strtok(NULL, delimiter);
    version = token;
    printf("Version: %s\n", version);

    while (token != NULL) {
      if (strstr(token, "Host:") != NULL) {
        token = strtok(NULL, delimiter);
        client_hostname = token;
        break;
      }
      token = strtok(NULL, delimiter);
    }

    printf("Client hostname: %s\n", client_hostname);