[C/C++] Backlog issue

I'm trying to come up with a good way to manage this buffer. However, with my current method, they are sometimes cut short, and there is a large backlog. For example, say the buffer contains "one\ntwo\nthree\nfour\n". It will process "one\n" and stop there. Then, when I recv five\n, it will finally process two\n. So on and so forth, it creates a huge backlog that processes older packets (finally) whenever it receives a new one. I'm fairly new to socket programming, and my buffer handling isn't quite up to par, I suppose. For anyone wondering, the reason it appends the buffer is because the end of the previous buffer may have a cut off command (for instance "sev", and the next receive will have "en\n"). If any of you could help me here, it'd be greatly appreciated. Function below.

bool sockRead()
{
    memset(tmpbuffer, '\0', strlen(tmpbuffer));
    length = recv(ircSocket, buffer, 2048,    0);
    if(length != SOCKET_ERROR)
    {

        char *scout = strncat(nbuffer, buffer, sizeof(nbuffer) - strlen(nbuffer) - 1);
        FILE *file;
        file = fopen("output.txt","a+");
        fprintf(file, "\nSCOUT: %s\n", scout);
        fclose(file);
        if(char *end = strchr(nbuffer, '\n') + 1)
        {
            strncpy(tmpbuffer, nbuffer, end - nbuffer);
            int x = strlen(nbuffer);
            memmove(nbuffer, end, x);
            nbuffer[x] = '\0';
            if(msgHandler() != true)
            {
                return false;
            }
        }
        return true;
    }
    printf("Line is dead.\n");
    return false;
}

On my knees

Begging for dubs

For anyone wondering, the reason it appends the buffer is because the end of the previous buffer may have a cut off command (for instance "e/g/", and the next receive will have "in\n"). If any of you could help me here, it'd be greatly appreciated.

1. you should be processing that in a loop

2. you should keep track of how much is left in the buffer and recv() at that offset, so that you don't overwrite old commands