[En-Nut-Discussion] unblocking get char

Ole Reinhardt ole.reinhardt at embedded-it.de
Thu Oct 11 09:49:13 CEST 2012

Hi Ayman,

> I need to add a function that not locking until the user input char through
> standard input, by another meaning  using getchar(); function will lock the
> thread until the user enter a char, I need the opposite that if the user
> was keep pressing a certain char, it will get that char if not, the
> execution will keep running without any blocking.

Please read http://www.ethernut.de/nutwiki/Advanced_UART_Functions,
especially the chapter about read timeouts.

You can set a timeout until which the read functions (and getchar is
only one of them) will return an error code instead of the char. 

Btw: Nut/OS uses more or less the same behaviour like other POSIX c-lib




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