2. FreeBSD Doc
3. books_developers-handbook

int listen(int s, int backlog);

int listen(int s, int backlog);

#define INADDR_ANY (u_int32_t)0x00000000

#define INADDR_ANY (u_int32_t)0x00000000

int bind(int s, const struct sockaddr *addr, socklen_t addrlen);

int bind(int s, const struct sockaddr *addr, socklen_t addrlen);

/*
* daytime.c
*
* Programmed by G. Adam Stanislav
*/
#include <stdio.h>
#include <string.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>

int main() {
register int s;
register int bytes;
struct sockaddr_in sa;
char buffer[BUFSIZ+1];

if ((s = socket(PF_INET, SOCK_STREAM, 0)) < 0) {
perror("socket");
return 1;
}

bzero(&sa, sizeof sa);

sa.sin_family = AF_INET;
sa.sin_port = htons(13);
sa.sin_addr.s_addr = htonl((((((192 << 8) | 43) << 8) | 244) << 8) | 18);
if (connect(s, (struct sockaddr *)&sa, sizeof sa) < 0) {
perror("connect");
close(s);
return 2;
}

while ((bytes = read(s, buffer, BUFSIZ)) > 0)
write(1, buffer, bytes);

close(s);
return 0;
}

/*
* daytime.c
*
* Programmed by G. Adam Stanislav
*/
#include <stdio.h>
#include <string.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>

int main() {
register int s;
register int bytes;
struct sockaddr_in sa;
char buffer[BUFSIZ+1];

if ((s = socket(PF_INET, SOCK_STREAM, 0)) < 0) {
perror("socket");
return 1;
}

bzero(&sa, sizeof sa);

sa.sin_family = AF_INET;
sa.sin_port = htons(13);
sa.sin_addr.s_addr = htonl((((((192 << 8) | 43) << 8) | 244) << 8) | 18);
if (connect(s, (struct sockaddr *)&sa, sizeof sa) < 0) {
perror("connect");
close(s);
return 2;
}

while ((bytes = read(s, buffer, BUFSIZ)) > 0)
write(1, buffer, bytes);

close(s);
return 0;
}

int connect(int s, const struct sockaddr *name, socklen_t namelen);

int connect(int s, const struct sockaddr *name, socklen_t namelen);

/*
* Internet address (a structure for historical reasons)
*/
struct in_addr {
in_addr_t s_addr;
};

/*
* Internet address (a structure for historical reasons)
*/
struct in_addr {
in_addr_t s_addr;
};

/*
* Socket address, internet style.
*/
struct sockaddr_in {
uint8_t sin_len;
sa_family_t sin_family;
in_port_t sin_port;
struct in_addr sin_addr;
char sin_zero[8];
};

/*
* Socket address, internet style.
*/
struct sockaddr_in {
uint8_t sin_len;
sa_family_t sin_family;
in_port_t sin_port;
struct in_addr sin_addr;
char sin_zero[8];
};

/*
* Address families.
*/
#define AF_UNSPEC 0 /* unspecified */
#define AF_LOCAL 1 /* local to host (pipes, portals) */
#define AF_UNIX AF_LOCAL /* backward compatibility */
#define AF_INET 2 /* internetwork: UDP, TCP, etc. */
#define AF_IMPLINK 3 /* arpanet imp addresses */
#define AF_PUP 4 /* pup protocols: e.g. BSP */
#define AF_CHAOS 5 /* mit CHAOS protocols */
#define AF_NS 6 /* XEROX NS protocols */
#define AF_ISO 7 /* ISO protocols */
#define AF_OSI AF_ISO
#define AF_ECMA 8 /* European computer manufacturers */
#define AF_DATAKIT 9 /* datakit protocols */
#define AF_CCITT 10 /* CCITT protocols, X.25 etc */
#define AF_SNA 11 /* IBM SNA */
#define AF_DECnet 12 /* DECnet */
#define AF_DLI 13 /* DEC Direct data link interface */
#define AF_LAT 14 /* LAT */
#define AF_HYLINK 15 /* NSC Hyperchannel */
#define AF_APPLETALK 16 /* Apple Talk */
#define AF_ROUTE 17 /* Internal Routing Protocol */
#define AF_LINK 18 /* Link layer interface */
#define pseudo_AF_XTP 19 /* eXpress Transfer Protocol (no AF) */
#define AF_COIP 20 /* connection-oriented IP, aka ST II */
#define AF_CNT 21 /* Computer Network Technology */
#define pseudo_AF_RTIP 22 /* Help Identify RTIP packets */
#define AF_IPX 23 /* Novell Internet Protocol */
#define AF_SIP 24 /* Simple Internet Protocol */
#define pseudo_AF_PIP 25 /* Help Identify PIP packets */
#define AF_ISDN 26 /* Integrated Services Digital Network*/
#define AF_E164 AF_ISDN /* CCITT E.164 recommendation */
#define pseudo_AF_KEY 27 /* Internal key-management function */
#define AF_INET6 28 /* IPv6 */
#define AF_NATM 29 /* native ATM access */
#define AF_ATM 30 /* ATM */
#define pseudo_AF_HDRCMPLT 31 /* Used by BPF to not rewrite headers
* in interface output routine
*/
#define AF_NETGRAPH 32 /* Netgraph sockets */
#define AF_SLOW 33 /* 802.3ad slow protocol */
#define AF_SCLUSTER 34 /* Sitara cluster protocol */
#define AF_ARP 35
#define AF_BLUETOOTH 36 /* Bluetooth sockets */
#define AF_MAX 37

/*
* Address families.
*/
#define AF_UNSPEC 0 /* unspecified */
#define AF_LOCAL 1 /* local to host (pipes, portals) */
#define AF_UNIX AF_LOCAL /* backward compatibility */
#define AF_INET 2 /* internetwork: UDP, TCP, etc. */
#define AF_IMPLINK 3 /* arpanet imp addresses */
#define AF_PUP 4 /* pup protocols: e.g. BSP */
#define AF_CHAOS 5 /* mit CHAOS protocols */
#define AF_NS 6 /* XEROX NS protocols */
#define AF_ISO 7 /* ISO protocols */
#define AF_OSI AF_ISO
#define AF_ECMA 8 /* European computer manufacturers */
#define AF_DATAKIT 9 /* datakit protocols */
#define AF_CCITT 10 /* CCITT protocols, X.25 etc */
#define AF_SNA 11 /* IBM SNA */
#define AF_DECnet 12 /* DECnet */
#define AF_DLI 13 /* DEC Direct data link interface */
#define AF_LAT 14 /* LAT */
#define AF_HYLINK 15 /* NSC Hyperchannel */
#define AF_APPLETALK 16 /* Apple Talk */
#define AF_ROUTE 17 /* Internal Routing Protocol */
#define AF_LINK 18 /* Link layer interface */
#define pseudo_AF_XTP 19 /* eXpress Transfer Protocol (no AF) */
#define AF_COIP 20 /* connection-oriented IP, aka ST II */
#define AF_CNT 21 /* Computer Network Technology */
#define pseudo_AF_RTIP 22 /* Help Identify RTIP packets */
#define AF_IPX 23 /* Novell Internet Protocol */
#define AF_SIP 24 /* Simple Internet Protocol */
#define pseudo_AF_PIP 25 /* Help Identify PIP packets */
#define AF_ISDN 26 /* Integrated Services Digital Network*/
#define AF_E164 AF_ISDN /* CCITT E.164 recommendation */
#define pseudo_AF_KEY 27 /* Internal key-management function */
#define AF_INET6 28 /* IPv6 */
#define AF_NATM 29 /* native ATM access */
#define AF_ATM 30 /* ATM */
#define pseudo_AF_HDRCMPLT 31 /* Used by BPF to not rewrite headers
* in interface output routine
*/
#define AF_NETGRAPH 32 /* Netgraph sockets */
#define AF_SLOW 33 /* 802.3ad slow protocol */
#define AF_SCLUSTER 34 /* Sitara cluster protocol */
#define AF_ARP 35
#define AF_BLUETOOTH 36 /* Bluetooth sockets */
#define AF_MAX 37

/*
* Structure used by kernel to store most
* addresses.
*/
struct sockaddr {
unsigned char sa_len; /* total length */
sa_family_t sa_family; /* address family */
char sa_data[14]; /* actually longer; address value */
};
#define SOCK_MAXADDRLEN 255 /* longest possible addresses */

/*
* Structure used by kernel to store most
* addresses.
*/
struct sockaddr {
unsigned char sa_len; /* total length */
sa_family_t sa_family; /* address family */
char sa_data[14]; /* actually longer; address value */
};
#define SOCK_MAXADDRLEN 255 /* longest possible addresses */

int socket(int domain, int type, int protocol);

int socket(int domain, int type, int protocol);