Thread: write and read system calls

Hello everyone.
I am trying to write a server-client program (INET)
I have all the connections ok but i have on e problem. When i try to pass binary data from the client to the server I dont know how to recognize whether I reached the EOF.

in my code:
ns is the file descriptor generated by accept() system call.
BUFSIZE is 256
buf is declared as char buf[BUFSIZE]
and fp is my FILE pointer. (the one I want to write.)

SERVER CODE(one part):

Code:

	
while( read(ns, buf, BUFSIZE) ){ 
		//printf("%s\n", buf); 
		fwrite(buf,sizeof(char),BUFSIZE,fp);
}

In the client buf and BUFSIZE are similar to the ones declared in the server. fp is the FILE pointer to the file i am trying to read. sockfd is the file descriptor generated by socket() system call. and the code is:

Code:

	while(fread(buf,sizeof(char),BUFSIZE,fp)!=0){
		write(sockfd, buf, BUFSIZE); 
		//printf("%s\n", buf); 
	}

I should say that in this part of code the server's read() waits for the client's write().

The problem is when i try to pass a file like this: (example.txt)

Code:

FILE FROM THE CLIENT 
FILE FROM THE CLIENT
FILE FROM THE CLIENT

i have as a result:

Code:

FILE FROM THE CLIENT 
FILE FROM THE CLIENT
FILE FROM THE CLIENT????????m??c???t??t??`???Z?????????????????0`H?Z?Z?????????|?????????????`????1?#0?m???????????h??????m?????funcs

And i suspect fwrite() function in the server needs something more.
Help please and thanks in advance

Code:

		write(sockfd, buf, BUFSIZE);

You probably want to write the count of bytes from read() instead of "BUFSIZE", as you will be writing out whatever else happens to be in buffer this way, which is exactly what it looks like you are doing.

--
Mats

OHHHHH!! sorry!, such a mistake.
so, should i get the number of bites read in an var (for example n) and for writing them i should write

Code:

 write(sockfd, buf, n);

is this correct?

Yes. Although I would make sure it's "greater than zero", rather than "not equal to zero" too - assuming your bufsize isn't bigger than 2GB...

--
Mats

thanks matsp