the story of a socket connect and a char array :-)

[Kifah Abbad]

This part finds the destination IP in a packet, and converts into a
string.



code:--------------------------------------------------------------------------------
char destination_IP[40]; //For saving destination IP
..
..
..
..
..


//save destination IP


sprintf(&Destination_IP_temp,"%d.%d.%d.%d",(vp->packet[30] &
0xff),(vp->packet[31] & 0xff),(vp->packet[32] & 0xff),(vp->packet[33]
& 0xff));
--------------------------------------------------------------------------------



Then i have a part for socket connection, that uses this IP in a
connect part:


code:--------------------------------------------------------------------------------
..
..
..
..
their_addr.sin_addr.s_addr = inet_addr(destination_IP);
memset(&(their_addr.sin_zero), '\0', 8); // zero the rest of the
struct

if (connect(sockfd, (struct sockaddr *)&their_addr, sizeof(struct
sockaddr)) == -1) {
perror("connect");
exit(1);
}
--------------------------------------------------------------------------------


But when i start proggie, it keeps exiting with error:


code:--------------------------------------------------------------------------------
connect: Invalid argument
--------------------------------------------------------------------------------


Although the ip gets printed out correctly when i try to debug with:

code:--------------------------------------------------------------------------------
printf("Destination %d.%d.%d.%d\n",
(vp->packet[30] & 0xff),
(vp->packet[31] & 0xff),
(vp->packet[32] & 0xff),
(vp->packet[33] & 0xff));

 

[Tom St Denis]

This part finds the destination IP in a packet, and converts into a
string.

<snip messy post>

You have to create a socket first [via socket()] before you can connect [you
connect the socket you made to the other end].

And this is OT for clc...

Tom

 

[Sean Kenwrick]

This part finds the destination IP in a packet, and converts into a
string.



code:-----------------------------------------------------------------------
---------
char destination_IP[40]; file://For saving destination IP
.
.
.
.
.


file://save destination IP


sprintf(&Destination_IP_temp,"%d.%d.%d.%d",(vp->packet[30] &
0xff),(vp->packet[31] & 0xff),(vp->packet[32] & 0xff),(vp->packet[33]
& 0xff));
-------------------------------------------------------------------------- ------

This looks suspicious. sprintf() tasks a pointer to a char as it's first
parameter not a pointer to a pointer to a char. Try
sprintf(Destination_IP_temp,"%d.%d....etc...);

Sean

 

[Kifah Abbad]

This part finds the destination IP in a packet, and converts into a
string.

<snip messy post>

You have to create a socket first [via socket()] before you can connect [you
connect the socket you made to the other end].

And this is OT for clc...

Thanks,

i did...i just did not post here

And i should add, that the programm worked fine with something like:


code:--------------------------------------------------------------------------------
their_addr.sin_addr.s_addr = inet_addr("10.10.10.11");
memset(&(their_addr.sin_zero), '\0', 8); // zero the rest of the
struct

--------------------------------------------------------------------------------

 

[Alan Balmer]

This part finds the destination IP in a packet, and converts into a
string.

<snip messy post>

You have to create a socket first [via socket()] before you can connect [you
connect the socket you made to the other end].

And this is OT for clc...

Thanks,

i did...i just did not post here

And i should add, that the programm worked fine with something like:

No, you shouldn't add that - it's still off-topic for c.l.c.

The C question in your original post seems to be why something you
call a "proggie" prints an "invalid argument" complaint about a
non-standard function named "connect."

1. Check that the argument types match the types specified in the
function prototype.

2. Check that the values of the arguments are correct.

If this doesn't help, try posting a question to a newsgroup where
"connect" is on-topic.