open/4 option: eof_action(Action) QP_stream: unsigned char peof_act
This field is only used for an input stream. There are three states for
an input stream, normal, end of file, and past end of file.
An input stream is in normal state until it reaches end of file, where
the state is switched to end of file state. If there is no file border
code or the file border code is consumed, the input stream is switched
to past end of file state. The field
peof_act specifies which
action to take for reading from a stream at past end of file state.
The value of
peof_act can be one of the following.
open/4. An error for any type of seeking in the stream.
errnofield of the stream is set to
QP_E_EXHAUSTED, and the read call fails.
open/4. Retuns the file border code for reading at the past end of file state. The state of the input stream does not change. If there is no file border code for the input stream, it is the same as setting the field to
open/4. Resets the state of an input stream to normal state and calls the bottom layer read function to get the input record for reading at past end of file state. Setting the field to this value may be useful for the stream with
QP_DELIM_TTYformat. It is possible to get more records from a tty device after the end of file character is typed.
Once an input stream reaches end of file state, its bottom layer read function
will not be called unless the
peof_act field is