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UnGetC -- Makes a char available for reading again. (buffered) (V36)
value = UnGetC(fh, character)
D0 D1 D2
LONG UnGetC(BPTR, LONG)
Pushes the character specified back into the input buffer. Every
time you use a buffered read routine, you can always push back 1
character. You may be able to push back more, though it is not
recommended, since there is no guarantee on how many can be
pushed back at a given moment.
Passing -1 for the character will cause the last character read to
be pushed back. If the last character read was an EOF, the next
character read will be an EOF.
Note: UnGetC can be used to make sure that a filehandle is set up
as a read filehandle. This is only of importance if you are writing
a shell, and must manipulate the filehandle's buffer.
fh - filehandle to use for buffered I/O
character - character to push back or -1
value - character pushed back, or FALSE if the character cannot
be pushed back.
In V36, UnGetC(fh,-1) after an EOF would not cause the next character
read to be an EOF. This was fixed for V37.
FGetC(), FPutC(), Flush()
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