Console I/O Protocol
Version 1.02 12/12/00 163
//*******************************************************
// EFI Required Arrow shapes
//*******************************************************
#define ARROW_UP 0x2191
#define ARROW_DOWN 0x2193
Description
The OutputString() function writes a Unicode string to the output device. This is the most
basic output mechanism on an output device. The String is displayed at the current cursor
location on the output device(s) and the cursor is advanced according to the following rules:
Mnemonic Unicode Description
Null U+0000 Ignore the character, and do not move the cursor.
BS U+0008 If the cursor is not at the left edge of the display, then move the cursor
left one column.
LF U+000A If the cursor is at the bottom of the display, then scroll the display one
row, and do not update the cursor position. Otherwise, move the cursor
down one row.
CR U+000D Move the cursor to the beginning of the current row.
Other U+XXXX Print the character at the current cursor position and move the cursor
right one column. If this moves the cursor past the right edge of the
display, then the line should wrap to the beginning of the next line. This
is equivalent to inserting a CR and an LF. Note that if the cursor is at the
bottom of the display, and the line wraps, then the display will be scrolled
one line.
If desired, the system’s NVRAM environment variables may be used at install time to determine
the configured locale of the system or the installation procedure can query the user for the proper
language support. This is then used to either install the proper EFI image/loader or to configure the
installed image’s strings to use the proper text for the selected locale.
Status Codes Returned
EFI_SUCCESS The string was output to the device.
EFI_DEVICE_ERROR The device reported an error while attempting to output
the text.
EFI_UNSUPPORTED The output device’s mode is not currently in a defined
text mode.
EFI_WARN_UNKNOWN_GLYPH This warning code indicates that some of the characters
in the Unicode string could not be rendered and were
skipped.