The type openmode is a bitmask type ([bitmask.types]). It contains the elements indicated in Table [tab:iostreams.openmode.effects].
Element | Effect(s) if set |
app | seek to end before each write |
ate | open and seek to end immediately after opening |
binary | perform input and output in binary mode (as opposed to text mode) |
in | open for input |
out | open for output |
trunc | truncate an existing stream when opening |