Questions for beginners ~ Why is this program wrong ~~ Problem canceled!

Questions for beginners ~ Why is this program wrong ~~ Problem canceled! -- Linux general technology-Linux programming and kernel information. The following is a detailed description. [I = s] This post was last edited by lang1437 at 2009-3-21 20:57.

The following section of the program is a port scan program I typed on Emacs, which may always cause errors ~ Later, I compiled a prompt in VC ++:
Fatal error C1083: Cannot open include file: 'unistd. H': No such file or directory
No header file ?? Why? That's right! Is the book wrong! I ignored a step!

# Include
# Include
# Include
# Include
# Include
# Include
# Include
# Include
# Include
# Include

// Define a port range
Typedef struct _ port_segment
{Struct in_addr dest_ip; // target IP Address
Unsigned short int min_port; // start Port
Unsigned short int max_port; // maximum Port
} Port_segment;
/* Custom error handling function */
Void my_err (const char * err_string, int line)
{Fprintf (stderr, "line: % d", line );
Perror (err_string );
Exit (1 );
}
/*
* Description: A function used to scan a port on an IP address.
* Return value:-1 error
* 0 the target port is not enabled
* 1 the target port is enabled
*/
Int do_scan (struct sockaddr_in serv_addr)
{Int conn_fd;
Int ret;
// Create a TCP socket
Conn_fd = socket (AF_INET, SOCK_STREAM, 0 );
If (conn_fd <0)
{My_err ("socket", _ LINE _);}
// Send a connection request to the server
If (ret = connect (conn_fd, (struct sockaddr *) & serv_addr, sizeof (struct sockaddr) <0)
{If (errno = ECONNREFUSED)
{// The target port is not enabled
Close (conn_fd );
Return 0;
}
Else
{// Other errors
Close (conn_fd );
Return-1;
}
}
Else if (ret = 0)
{Printf ("port % d found in % s \ n", ntohs (serv_addr.sin_port), inet_ntoa (serv_addr.sin_addr ));
Close (conn_fd );
Return 1;
}
Return-1; // the actual execution is not here, just to eliminate the warning generated when compiling the program
}
// The thread that executes the scan to scan the port of a certain interval
Void * scaner (woid * arg)
{Unsigned short int I;
Struct sockaddr_in serv_addr;
Port_segment portinfo; // port information
// Read the port range information
Memcpy (& portinfo, arg, sizeof (struct_port_segment ));
// Initialize the server address Structure
Memset (& serv_addr, 0, sizeof (struct sockaddr_in ));
Serv_addr.sin_family = AF_INET;
Serv_addr.sin_addr = portinfo. dest_ip.s_addr;
For (I = porinfo. min_port; I <= portinfo. max_port; I ++)
{Serv_addr.sin_port = htons (I );
If (do_scan (serv_addr) <0)
{Continue; // exit the process if an error occurs.
}
}
Return NULL;
}
/* Command line parameter:-m maximum port,-a destination host IP address,-n maximum number of threads */
Int main (int argc, char ** argv)
{
Pthread_t * thread; // point to all thread IDS
Int max_port; // The maximum port number.
Int thread_num; // The maximum number of threads.
Int seg_len; // port Interval Length
Structin_addr dest_ip; // target host IP Address
Int I; // check the number of parameters
If (argc! = 7)
{Printf ("Usage: [-m] [max_port] [-a] [serv_address] [-n] [thread_number] \ n ");
Exit (1 );
}
// Parse command line parameters
For (I = 1; I {if (strcmp ("-m", argv ) = 0)
{Max_port = atoi (argv [I + 1]);
Printf ("Usafe: invalid max dest port \ n ");
Exit (1 );
}
Continue;
}
If (strcmp ("-a", argv= 0) = 0 ){
If (inet_aton (argv [I + 1], & dest_ip) = 0 {
Printf ("Usage: invalid dest ip address \ n ");
Exit (1 );
}
Continue;
}
If (strcmp ("-n", argv) = 0 ){
Thread_num = atoi (argv [I + 1]);
If (thread_num <= 0 ){
Printf ("Usage: invalid thread_number \ n ");
} Continue;
}
}
// If the input maximum port number is smaller than the number of threads, set the number of threads to the maximum port number.
If (max_port Thread_num = max_port;
}
Seg_len = max_port/thread_num;
If (max_port % thread_num )! = 0 ){
Thread_num + = 1;
}
// Allocate memory space for storing all thread IDS
Thread = (pthread_t *) malloc (thread_num * sizeof (pthread_t ));
// Create a thread and allocate the port range scanned by each thread based on the maximum port number and number of threads
For (I = 0; I {Port_segment portinfo;
Portinfo. dest_ip = dest_ip;
Portinfo. min_port = I * seg_len + 1;
If (I = thread_num-1)
{Portinfo. max_port = max_port ;}
Else {
Portinfo. max_port = portinfo. min_port + seg_len-1;
}
// Create a thread
If (pthread_create (& thread, NULL, scaner, (void *) & portinfo )! = 0)
{My_err ("pthread_create", _ LINE _);}
// The main thread waits for the sub-thread to end
Pthread_jion (thread, NULL );
}
Retun 0;
}