3.2.1. Digital TV demux open()¶
3.2.1.1. Name¶
Digital TV demux open()
3.2.1.3. Arguments¶
name
- Name of specific Digital TV demux device.
flags
- A bit-wise OR of the following flags:
O_RDONLY |
read-only access |
O_RDWR |
read/write access |
O_NONBLOCK |
open in non-blocking mode (blocking mode is the default) |
3.2.1.4. Description¶
This system call, used with a device name of /dev/dvb/adapter?/demux?
,
allocates a new filter and returns a handle which can be used for
subsequent control of that filter. This call has to be made for each
filter to be used, i.e. every returned file descriptor is a reference to
a single filter. /dev/dvb/adapter?/dvr?
is a logical device to be used
for retrieving Transport Streams for digital video recording. When
reading from this device a transport stream containing the packets from
all PES filters set in the corresponding demux device
(/dev/dvb/adapter?/demux?
) having the output set to DMX_OUT_TS_TAP
.
A recorded Transport Stream is replayed by writing to this device.
The significance of blocking or non-blocking mode is described in the
documentation for functions where there is a difference. It does not
affect the semantics of the open()
call itself. A device opened
in blocking mode can later be put into non-blocking mode (and vice versa)
using the F_SETFL
command of the fcntl system call.
3.2.1.5. Return Value¶
On success 0 is returned.
On error -1 is returned, and the errno
variable is set
appropriately.
EMFILE |
“Too many open files”, i.e. no more filters available. |
The generic error codes are described at the Generic Error Codes chapter.