io_receivefd(3) [debian man page]

io_receivefd(3) 					     Library Functions Manual						   io_receivefd(3)

NAME

       io_receivefd - receive a file descriptor over a Unix Domain socket

SYNTAX

       #include <io.h>

       int64 io_receivefd(int64 sock);

DESCRIPTION

       io_receivefd receives a file descriptor from the Unix Domain socket sock.  You can send a descriptor using io_passfd(3).

       io_receivefd returns -1 on error or the file descriptor.

       The underlying Unix API can send more than one descriptor at the time.  This function expects only one descriptor and will return the first
       one if more than one were sent.

SEE ALSO

       io_passfd(3)

																   io_receivefd(3)

io_tryread(3)						     Library Functions Manual						     io_tryread(3)

NAME

       io_tryread - read from a descriptor without blocking

SYNTAX

       #include <io.h>

       int io_tryread(int64 fd,char* buf,int64 len);

DESCRIPTION

       io_tryread  tries to read len bytes of data from descriptor fd into buf[0], buf[1], ..., buf[len-1]. (The effects are undefined if len is 0
       or smaller.) There are several possible results:

       o  o_tryread returns an integer between 1 and len: This number of bytes was available for immediate reading; the bytes were read  into  the
	  beginning  of  buf. Note that this number can be, and often is, smaller than len; you must not assume that io_tryread always succeeds in
	  reading exactly len bytes.

       o  io_tryread returns 0: No bytes were read, because the descriptor is at end of file. For example, this descriptor has reached the end	of
	  a disk file, or is reading an empty pipe that has been closed by all writers.

       o  io_tryread  returns -1, setting errno to EAGAIN: No bytes were read, because the descriptor is not ready. For example, the descriptor is
	  reading an empty pipe that could still be written to.

       o  io_tryread returns -3, setting errno to something other than EAGAIN: No bytes were read, because the read attempt encountered a  persis-
	  tent error, such as a serious disk failure (EIO), an unreachable network (ENETUNREACH), or an invalid descriptor number (EBADF).

       io_tryread does not pause waiting for a descriptor that is not ready.  If you want to pause, use io_waitread or io_wait.

       You can make io_tryread faster and more efficient by making the socket non-blocking with io_nonblock().

SEE ALSO

       io_nonblock(3), io_waitread(3), io_tryreadtimeout(3)

																     io_tryread(3)