Metrologic Optimus R, Руководство по программированию

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148 "C" Programming Guide For Optimus S/R
See Also accept, getpeername, getsockname, listen, select, socket
fcntlsocket
Purpose To provide file control over descriptors.
Syntax int fcntlsocket (int fildes, int cmd, int arg);
Example (?)
Description The routine provides for control over descriptors.
The argument
fildes
is a descriptor to be operated on by cmd as described
below.
cmd
O_NDELAY non-blocking (?)
FNDELAY O_NDELAY synonym (?)
F_GETFL Get descriptor status flags (arg is ignored).
F_SETFL Set descriptor status flags to arg.
Depending on the value of cmd, it can take an additional third argument
arg .
Return
If successful, it returns a non-negative value depending on
cmd
.
Otherwise, it returns -1.
The global variable errno is set to indicate the error condition encountered.
See Also
gethostbyname
Purpose To get network host entry.
Syntax
struct hostent *gethostbname (const char *hnp);
hnp Pointer to a buffer containing a null-terminated host name
Example SOCKET s;
struct sockaddr_in name;
struct hostent *phostent;
s = socket (PF_INET, SOCK_STREAM, TCP);
if (s < 0) {
printf ("SOCKET allocation failed");
.......................
}
memset (&name, 0, sizeof (name));