zephyr/samples/subsys/console/getline
Keith Packard 0b90fd5adf samples, tests, boards: Switch main return type from void to int
As both C and C++ standards require applications running under an OS to
return 'int', adapt that for Zephyr to align with those standard. This also
eliminates errors when building with clang when not using -ffreestanding,
and reduces the need for compiler flags to silence warnings for both clang
and gcc.

Most of these changes were automated using coccinelle with the following
script:

@@
@@
- void
+ int
main(...) {
	...
-	return;
+	return 0;
	...
}

Approximately 40 files had to be edited by hand as coccinelle was unable to
fix them.

Signed-off-by: Keith Packard <keithp@keithp.com>
2023-04-14 07:49:41 +09:00
..
src samples, tests, boards: Switch main return type from void to int 2023-04-14 07:49:41 +09:00
CMakeLists.txt
prj.conf
README.rst
sample.yaml

.. _console_getline_sample:

console_getline() Sample Application
####################################

Overview
********

This example shows how to use :c:func:`console_getline` function.
Similar to the well-known ANSI C gets() and fgets() functions,
:c:func:`console_getline` either returns the next available input
line or blocks waiting for one. Using this function, it should be fairly
easy to port existing ANSI C, POSIX, or Linux applications which process
console input line by line. The sample also allows to see details of how
a line is returned by the function.

If you are interested in character by character console input, see
:ref:`console_getchar_sample`.


Requirements
************

UART console is required to run this sample.


Building and Running
********************

The easiest way to run this sample is using QEMU:

.. zephyr-app-commands::
   :zephyr-app: samples/subsys/console/getline
   :host-os: unix
   :board: qemu_x86
   :goals: run
   :compact:

Now start pressing keys on a keyboard, followed by Enter. The input line
will be printed back, with a hex code of the last character, to show that
line does not include any special "end of line" characters (like LF, CR,
etc.)
Exit QEMU by pressing :kbd:`CTRL+A` :kbd:`x`.