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gethostbyname(s tring here)

Hello,

I have one problem, and can think of two possible solutions but I
can't manage to make them work. I'm open to other suggestions if you
thik is better.

[Brief Situation] The main function calls sendSocket, but I don't know
how to tell it where to send the socket. ( I think I'm messing it up
with pointers)

struct hostent *hp;

sendSocket(){
hp= gethostbyname(P ROBLEM HERE);
}

main(){
sendSocket();
}

[Possible First Solution]
This would be probably the best approach to what I need. Ask the user
for the hostname

sendSocket(){
char hostname[256];
printf("Enter hostname: ");
fgets ( hostname, 256, stdin );
hp= gethostbyname(¿ WHAT SHOULD I PUT HERE?);
}

[Possible Second Solution]
A way to make argc and argv available outside the main function.

struct hostent *hp;
sendSocket(){
hp = gethostbyname(a rgv[1]);
}
main(int argc; char *argv[]){
sendSocket();
}

Any suggestion? Thanks

Nov 15 '05 #1
5 2744
ru****@gmail.co m wrote:
Hello,

I have one problem, and can think of two possible solutions but I
can't manage to make them work. I'm open to other suggestions if you
thik is better.

[Brief Situation] The main function calls sendSocket, but I don't know
how to tell it where to send the socket. ( I think I'm messing it up
with pointers)

struct hostent *hp;

sendSocket(){
hp= gethostbyname(P ROBLEM HERE);
}

main(){ int main(void) { sendSocket();
}


As such things are handled in a platform specific way (they are not part
of standard C) please ask in a forum specific to your platform.

[And, of course, you *should* have read the FAQ before posting.]

HTH,
--ag

--
Artie Gold -- Austin, Texas
http://goldsays.blogspot.com (new post 8/5)
http://www.cafepress.com/goldsays
"If you have nothing to hide, you're not trying!"
Nov 15 '05 #2
TKS
Hi,

Sorry. I found that the cause why the first solution didn't work was
the '\n' being introduced in the last position before '\0'.

Thank you Artie. I read the FAQ but didn't find anything about this,
sorry if this wasn't the appropriate group.

Bye

Nov 15 '05 #3
Artie Gold wrote:

ru****@gmail.co m wrote:
Hello,

I have one problem, and can think of two possible solutions but I
can't manage to make them work. I'm open to other suggestions if you
thik is better.

[Brief Situation] The main function calls sendSocket, but I don't know
how to tell it where to send the socket. ( I think I'm messing it up
with pointers)
[...] As such things are handled in a platform specific way (they are not part
of standard C) please ask in a forum specific to your platform.

[And, of course, you *should* have read the FAQ before posting.]


While the example is using gethostbyname() , the real question being
asked is "how can I get a string from the user, and pass it to a
function", which would certainly not be off-topic. The fact that
the function is gethostbyname() and not print_foo(), is irrelevant
in this instance.

His followup post showed he found the correct answer -- that fgets()
leaves the newline intact, and he had to remove it before passing the
string to the function.
--
+-------------------------+--------------------+-----------------------------+
| Kenneth J. Brody | www.hvcomputer.com | |
| kenbrody/at\spamcop.net | www.fptech.com | #include <std_disclaimer .h> |
+-------------------------+--------------------+-----------------------------+
Don't e-mail me at: <mailto:Th***** ********@gmail. com>
Nov 15 '05 #4
Kenneth Brody wrote:
Artie Gold wrote:
ru****@gmail. com wrote:
Hello,

I have one problem, and can think of two possible solutions but I
can't manage to make them work. I'm open to other suggestions if you
thik is better.

[Brief Situation] The main function calls sendSocket, but I don't know
how to tell it where to send the socket. ( I think I'm messing it up
with pointers)


[...]
As such things are handled in a platform specific way (they are not part
of standard C) please ask in a forum specific to your platform.

[And, of course, you *should* have read the FAQ before posting.]

While the example is using gethostbyname() , the real question being
asked is "how can I get a string from the user, and pass it to a
function", which would certainly not be off-topic. The fact that
the function is gethostbyname() and not print_foo(), is irrelevant
in this instance.

His followup post showed he found the correct answer -- that fgets()
leaves the newline intact, and he had to remove it before passing the
string to the function.

Point taken.

However, even in a case like that, it behooves the OP to provide a
visible prototype for any non-standard function (yes I know what
gethostbyname() does -- but not when I'm wearing this hat ;-)).

Cheers,
--ag

--
Artie Gold -- Austin, Texas
http://goldsays.blogspot.com (new post 8/5)
http://www.cafepress.com/goldsays
"If you have nothing to hide, you're not trying!"
Nov 15 '05 #5
Artie Gold <ar*******@aust in.rr.com> wrote:

# However, even in a case like that, it behooves the OP to provide a
# visible prototype for any non-standard function (yes I know what
# gethostbyname() does -- but not when I'm wearing this hat ;-)).

When you find yourself in a hole, stop digging.

--
SM Ryan http://www.rawbw.com/~wyrmwif/
What kind of convenience store do you run here?
Nov 15 '05 #6

This thread has been closed and replies have been disabled. Please start a new discussion.

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