accepting input while writing to screen

i am still doing basic programs just to see what i can do, and i wanted to write a small little chat program. how would i accept the user typing in a message, and still let the server send out messages from other users?

i only know scanf, and scanf pauses the program from running untill the user enters something. i need the messages to be updated while the user is typing, or else it isnt much of an instand messenger.

thanks

Look in to threading. It let's you have two parts of your program running simulataneously. Of course, I wouldn't recommend this if you still consider yourself a newbie to the language,

ill start reading up on threading, but it seems like it is alot of work for just a stupid little chating program.

you can try something like..

Code:

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char c[256];
 int i=0;
 while((c[i]=getchar())!='\n')
  i++;

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would \n be the user hitting enter then?

Quote:

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Originally Posted by variable

would \n be the user hitting enter then?

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yes, thats the user pressing enter. also, be sure to check whether the array is completely filled. you could also use dynamic memory allocation if you dont want to put a maximum length limit.

PING, the input function is blocking - you can't do anything until the input function returns, and it won't return unless the user presses enter. This doesn't do the job for a chat program.

aye, true, it would have to be threaded then eh?

the input function?? which one is that ??

i think he means getchar()

Code:

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while((c[i]=getchar())!='\n')
  i++;

---

Nothing else in your program is going to happen while this loop is being implemented. That is what sean is talking about when he says your input function is blocking.

of course, for that he will look into threading..cant deny that

yep, well it looks like im off to read up on some multithreading.

anyone know if allegro and wsock32 can work together?

this code will not work

Code:

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#include <allegro.h>
#include <windows.h>
#include <winsock.h>
#include <stdio.h>

int main (void)
{
    WORD sockVersion;
        WSADATA wsaData;
        int nret;
        char buffer[256];
       
    allegro_init();
    install_keyboard();
       
        sockVersion = MAKEWORD(1, 1);
       
        WSAStartup(sockVersion, &wsaData);
       
        SOCKET mysocketa1;
       
        mysocketa1 = socket( AF_INET , SOCK_STREAM , IPPROTO_TCP );
       
        SOCKADDR_IN serverInfo;

        serverInfo.sin_family = AF_INET;
        serverInfo.sin_port = htons(8888);
        serverInfo.sin_addr.s_addr = inet_addr("10.1.50.30");
       
        ZeroMemory(buffer, 256);
       
        scanf("%s", &buffer[0]);
        scanf("%s", &buffer[1]);
        printf("%s",buffer);
       
        connect(mysocketa1, (LPSOCKADDR)&serverInfo , sizeof(struct sockaddr));
   
    send( mysocketa1 , buffer , strlen(buffer) , 0 );       
       
       
        closesocket(mysocketa1);
       
        WSACleanup();
        getch();
       
        allegro_exit();
       
        return 0;
       
}
END_OF_MAIN();

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it only gives errors when i use allegro with it.

wanted to do this so that i could use the nonblocking functions in allegro.

I don't know if it would work or not using allgero and winsock, but you might want to try sdl and sdl_net combination instead if it wont.

ok, thanks; ill keep trying to make allegro work, and then if i cant get it to work, i will fall back to the sdl

Threading is not difficult per-se, it requires thought and planning however, resources most newbies are unwilling to provide, they want a quick fix.

I have a very basic Windows threading tutorial on my site, starting here. It is written in C++ but if you change the headers and the cout's to printf's it will work. There is nothing language specific about the API's used.

If you are using a *nix system, search for pThreads - most of the ideas are the same.

ok, cool, will read, thanks