Simple_Text_Output.teststring() - Intel Extensible Firmware Interface Specification

Extensible Firmware Interface Specification
7.5.3

SIMPLE_TEXT_OUTPUT.TestString()

Summary
Verifies that all characters in a Unicode string can be output to the target device.
Prototype
EFI_STATUS
(EFIAPI *EFI_TEXT_TEST_STRING) (
IN SIMPLE_TEXT_OUTPUT_INTERFACE *This,
IN CHAR16
);
Parameters
This
String
Description
The
TestString()
target device.
This function provides a way to know if the desired character set is present for rendering on the
output device(s). This allows the installation procedure (or EFI image) to at least select a letter set
that the output devices are capable of displaying. Since the output device(s) may be changed
between boots, if the loader cannot adapt to such changes it is recommended that the loader call
OutputString()
that are capable of displaying the Unicode letter set will do so.
Status Codes Returned
EFI_SUCCESS
EFI_UNSUPPORTED
164
A pointer to the
SIMPLE_TEXT_OUTPUT_INTERFACE
Type
SIMPLE_TEXT_OUTPUT_INTERFACE
The Null-terminated Unicode string to be examined for the output
device(s).
function verifies that all characters in a Unicode string can be output to the
with the text it has and ignore any "unsupported" error codes. The devices(s)
The device(s) are capable of rendering the output string.
Some of the characters in the Unicode string cannot be rendered
by one or more of the output devices mapped by the EFI handle.
12/12/00
*String
is defined in Section 7.5.
Version 1.02
instance.