Working with the Unix OS

Interprocess Communication
Address Conversion Routines
#include
#include
#include
/* convert character string in dotted decimal notation to/from 32-bit Internet
address */
unsigned long inet_addr(char *ptr);
char *inet_ntoa(struct in_addr inaddr);
A Simple Example
1. The client reads a line from its standard input and writes the line to the server.
2. The server reads a line from its network input and echoes the line back to the client.
3. The client reads the echoed line and prints it on its standard output.
4. This is known as an echo server. The example shows a concurrent server using connection-oriented
Internet.
Utility Routines
Read or writing n bytes to or from a stream socket.
int readn(int sockfd, char *ptr, int nbytes);
int writen(int sockfd, char *ptr, int nbytes);
int readline(int sockfd, char *ptr, int maxlen);
Note that readline function issues one read system call for every byte of data.
Would like to buffer the data using a read system call to read as much data as it can, and then examine the
buffer one byte at a time.
Read a stream socket one line at a time, and write each line back to the sender.
str_echo(int sockfd);
Read contents of FILE, write each line to stream socket, then read line back from socket and write to standard
out.
str_cli(FILE *fd, int sockfd);
Stream Pipes
int s-pipe(int fd[2]); /* unnamed stream pipe */
int ns-pipe(int fd[2]); /* named stream pipe */
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