The GNU C Library - Socket Data Options

Socket Data Options

The flags argument to send and recv is a bit mask. You can bitwise-OR the values of the following macros together to obtain a value for this argument. All are defined in the header file `sys/socket.h'.

Macro int MSG_OOB

Send or receive out-of-band data. See Out-of-Band Data.

Macro int MSG_PEEK

Look at the data but don't remove it from the input queue. This is only meaningful with input functions such as recv , not with send .

Macro int MSG_DONTROUTE

Don't include routing information in the message. This is only meaningful with output operations, and is usually only of interest for diagnostic or routing programs. We don't try to explain it here.