Commodore 1541-II - Page 61

Get# may be especially useful in recovering damaged files, or files with unknown
contents. The Basic reserved variable ST (the file STatus variable) can be used to indicate
when all of a properly-closed file has been read.
500 GET#2,S$
510 SU = ST:REM REMEMBER FILE STATUS
520 PRINT S$;
530 IF SU = 0 THEN 500:REM IF THERE'S MORE TO BE REAL
540 IF SUO64 THEN PRINT "STATUS ERROR: ST = ";SU
Copying ST into SU is often an unneccessary precaution, but must be done if any other
file-handling statement appears between the one which read from the file and the one that
loops back to read again. For example, it would be required if line 520 was changed to
520PRINT#l,S$;
Otherwise, the file status checked in line 530 would be that of the write file, not the read
file.
POSSIBLE VALUES OF THE FILE STATUS VARIABLE t4ST",
IFST =
0
1
2
4
8
16
32
64
128
AND THEIR MEANINGS
THEN
All is OK
Receiving device was not available (time out on talker)
Transmitting device was not available (time out on listener)
Cassette data file block was too short
Cassette data file block was too long
Unrecoverable read error from cassette, verify error
Cassette checksum error—one or more faulty characters were read
End of file reached (EOI detected)
Device not present, or end of tape mark found on cassette
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