Write a program to make the UDP client program in Table 25.2 more generic to be able to send any request created by the client program.

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Table 25.2 Echo client program using UDP I/ UDP echo client program #include "headerFiles.h" int main (int arge, char* argv[ ]) // Three arguments to be checked later // Declare and define variables int s; I/ Socket descriptor 6. // Length of string to be echoed // Server name int len; char* servName; I/ Server port // String to be echoed // Data buffer // Server socket address int servPort; char* string; char buffer [256 + 1]; 10 12 struct sockaddr_in servAddr; I/ Check and set program arguments if (argc != 3) 13 14 15 16 printf ("Error: three arguments are needed!"); exit(1): servName=argv[1]; servPort = atoi (argv[2]); string = argv[3]; // Build server socket address memset (&servVAddr, 0, sizeof (servAddr)): servAddr.sin_family = AF_INET; inet_pton (AF_INET, servName, &servAddr.sin addr); servAddr.sin port = htons (servPort): // Create socket if ((s = socket (PF_INET, SOCK_DGRAM, 0) < 0); perror ("Error: Socket failed!"): exit (1); I/ Send echo string len = sendto (s, string, strlen (string), 0, (struct sockaddr)&servAddr, sizeof (servAddr)); I/ Receive echo string recvfrom (s, buffer, len, 0, NULL, NULL); // Print and verify echoed string 38 buffer [len] = "0'; printf ("Echo string received: "; fputs (buffer, stdout); I/ Close the socket 40 41 close (s);s 43 // Stop the program 44 exit (0): 45 J// End of echo client program