socket getservent sample c code

/*

 * getservent.c:

 * Example getservent(3) program:

 */

  #include <stdio.h>

  #include <unistd.h>

  #include <stdlib.h>

  #include <errno.h>

  #include <string.h>

  #include <time.h>

  #include <sys/types.h>

  #include <sys/socket.h>

  #include <netinet/in.h>

  #include <arpa/inet.h>

  int main(int argc, char **argv) {

     int x;

     struct servent *sp;

     for (;;) {

        errno = 0;

        if ( !(sp = getservent()) ) {

           break;

        }

        printf("%s:\n"

               "\tPort: %d\n"

               "\tProtocol: %s\n"

               "\tAliases: ",

               sp->s_name,

               ntohs(sp->s_port),

               sp->s_proto);

        for ( x=0; sp->s_aliases[x] != NULL; ++x ) {

           printf("%s ",sp->s_aliases[x]);

        }

        putchar('\n');

     }

     if ( errno != 0 && errno != ENOENT ) { /* For RH-6.0 */

        fprintf(stderr,

                "%s: getservent(3) %d\n",

                strerror(errno),errno);

     }

     return 0;

  }

/*

 * OUTPUT

 * 

[sgupta@rhel55x86 chap7]$ gcc -o getservent getservent.c

[sgupta@rhel55x86 chap7]$ ./getservent

tcpmux:

        Port: 1

        Protocol: tcp

        Aliases:

tcpmux:

        Port: 1

        Protocol: udp

        Aliases:

rje:

        Port: 5

        Protocol: tcp

        Aliases:

rje:

        Port: 5

        Protocol: udp

        Aliases:

echo:

        Port: 7

        Protocol: tcp

        Aliases:

echo:

        Port: 7

        Protocol: udp

        Aliases:

discard:

        Port: 9

        Protocol: tcp

        Aliases: sink null

 iqobject:

        Port: 48619

        Protocol: udp

        Aliases:

[sgupta@rhel55x86 chap7]$

 */