pSOSystem System Calls - Read

ecvfrom pNA+ System Calls
recvfrom Receives data from a socket.
#include
long recvfrom(
int s, /* socket descriptor */
char *buf, /* packet buffer */
int len, /* packet buffer length */
int flags, /* packet attributes */
struct sockaddr_in *from, /* sender attributes */
int *fromlen /* number of bytes recieved */
)
Description
Arguments
The recvfrom() system call is used to receive data from a socket. This system call
is almost identical to recv(). The difference is recvfrom() may also return the
address of the sender in the specified parameter.
s Specifies the socket from which data is received. The behavior of
the system call depends on the socket type. Refer to recv() for
more information.
buf Points to the user buffer where data is stored.
len Specifies the size of the buffer in bytes.
flags Specifies usage options and is the result of an OR operation performed
on one or more of the following symbolic constants (defined
in ). Can also be set to 0.
MSG_OOB Specifies that you want recvfrom() to read
any out-of-band data present on the socket,
rather than the regular in-band data.
MSG_PEEK Specifies that you want recvfrom() to peek at
the data present on the socket; the data is returned,
but not consumed, so that a subsequent
receive operation sees the same data.
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