40 lines
2 KiB
Text
40 lines
2 KiB
Text
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Software cursor for VGA by Pavel Machek <pavel@atrey.karlin.mff.cuni.cz>
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======================= and Martin Mares <mj@atrey.karlin.mff.cuni.cz>
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Linux now has some ability to manipulate cursor appearance. Normally, you
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can set the size of hardware cursor (and also work around some ugly bugs in
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those miserable Trident cards--see #define TRIDENT_GLITCH in drivers/video/
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vgacon.c). You can now play a few new tricks: you can make your cursor look
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like a non-blinking red block, make it inverse background of the character it's
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over or to highlight that character and still choose whether the original
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hardware cursor should remain visible or not. There may be other things I have
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never thought of.
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The cursor appearance is controlled by a "<ESC>[?1;2;3c" escape sequence
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where 1, 2 and 3 are parameters described below. If you omit any of them,
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they will default to zeroes.
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Parameter 1 specifies cursor size (0=default, 1=invisible, 2=underline, ...,
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8=full block) + 16 if you want the software cursor to be applied + 32 if you
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want to always change the background color + 64 if you dislike having the
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background the same as the foreground. Highlights are ignored for the last two
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flags.
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The second parameter selects character attribute bits you want to change
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(by simply XORing them with the value of this parameter). On standard VGA,
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the high four bits specify background and the low four the foreground. In both
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groups, low three bits set color (as in normal color codes used by the console)
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and the most significant one turns on highlight (or sometimes blinking--it
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depends on the configuration of your VGA).
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The third parameter consists of character attribute bits you want to set.
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Bit setting takes place before bit toggling, so you can simply clear a bit by
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including it in both the set mask and the toggle mask.
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Examples:
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=========
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To get normal blinking underline, use: echo -e '\033[?2c'
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To get blinking block, use: echo -e '\033[?6c'
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To get red non-blinking block, use: echo -e '\033[?17;0;64c'
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