Incorrect while condition

[nick048]

Hi to all,

I have founded a problem in my program; it is in this code:

i=0;
charRecv = recv(nSocketDesc, &c, 1, 0);
while (c !='\n')
{
mystring[i++]=c;
charRecv = recv(nSocketDesc, &c, 1, 0);
} // End while (c !='\n')
mystring[i]='\0';

I need that while ends when the client press enter key.
But don't happen therefore.Sure, I mistake the condition in "while".
Please, someone can help me?
Thank You and Best Regards.
Gaetano

[Walter Roberson]

In article <11**********************@l77g2000hsb.googlegroups .com>,
nick048 <ni*************@moonsoft.itwrote:

>I have founded a problem in my program; it is in this code:

>i=0;
charRecv = recv(nSocketDesc, &c, 1, 0);
while (c !='\n')
{
mystring[i++]=c;
charRecv = recv(nSocketDesc, &c, 1, 0);
} // End while (c !='\n')
mystring[i]='\0';

>I need that while ends when the client press enter key.
But don't happen therefore.Sure, I mistake the condition in "while".
Please, someone can help me?

recv is not part of standard C, so as far as this newsgroup is
concerned, we don't know what it does. You should talk to people
who deal with whichever operating system extension is providing
recv() to your program.

In particular, since we don't know what recv() does, we don't
know that when the user presses the enter key that \n is the
character that is sent. It is plausible that when the
user presses the enter key, that \r is sent instead, or some
multi-character code that represents the enter key.

Glacing at the program, I also see a different possibility: namely,
that there might be input buffering on the side of whatever is
providing data to the recv(), so when the user is pressing
the enter key, the data is not necessarily transmitted to the
far end.

A typical way to debug a problem such as this would be to
print out the value of c after the recv(), in a couple of different
formats, so that you can see what value is getting to you and
with what timing.
--
Okay, buzzwords only. Two syllables, tops. -- Laurie Anderson

[Ben Bacarisse]

"nick048" <ni*************@moonsoft.itwrites:

Hi to all,

I have founded a problem in my program; it is in this code:

i=0;
charRecv = recv(nSocketDesc, &c, 1, 0);
while (c !='\n')
{
mystring[i++]=c;
charRecv = recv(nSocketDesc, &c, 1, 0);
} // End while (c !='\n')
mystring[i]='\0';

I need that while ends when the client press enter key.
But don't happen therefore.Sure, I mistake the condition in "while".

You problem has only a very little to do with standard C (the topic of
this group) and a lot to do with how to program using sockets (and how
they interact with your OS).

Please, someone can help me?

You will do better over in comp.unix.programmer or at least a group
dedicated to the OS that is hosting your program.

--
Ben.

[mike]

On Apr 10, 9:48 am, "nick048" <[e-mail]:

Hi to all,

I have founded a problem in my program; it is in this code:

i=0;
charRecv = recv(nSocketDesc, &c, 1, 0);
while (c !='\n')
{
mystring[i++]=c;
charRecv = recv(nSocketDesc, &c, 1, 0);
} // End while (c !='\n')
mystring[i]='\0';

I need that while ends when the client press enter key.
But don't happen therefore.Sure, I mistake the condition in "while".
Please, someone can help me?
Thank You and Best Regards.
Gaetano

It looks like you are using the recv() as referenced by the MSDN
article: http://msdn2.microsoft.com/en-us/library/ms740121.aspx

They have an example of how it works. charRecv will be 0 or negative
when there is nothing else to read. You could use that to end the
loop. Look at the examples in the article.

[SM Ryan]

"nick048" <ni*************@moonsoft.itwrote:
# Hi to all,
#
# I have founded a problem in my program; it is in this code:
#
# i=0;
# charRecv = recv(nSocketDesc, &c, 1, 0);
# while (c !='\n')
# {

You can add something like
fprintf(stderr,"charRecv=%d c=%02X %c\n",charRecv,c,c);
and know exactly what c is being set to and why the loop isn't
ending the way you expect. You can guess what is happening
or find out for sure.

# mystring[i++]=c;
# charRecv = recv(nSocketDesc, &c, 1, 0);
# } // End while (c !='\n')
# mystring[i]='\0';
#
# I need that while ends when the client press enter key.
# But don't happen therefore.Sure, I mistake the condition in "while".
# Please, someone can help me?
# Thank You and Best Regards.
# Gaetano
#
#
#

--
SM Ryan http://www.rawbw.com/~wyrmwif/
I ASSURE YOU WE'RE OPEN!