Category : Files from Magazines
Archive   : VOL7N12.ZIP
Filename : SEEKTEXT.PAS

 
Output of file : SEEKTEXT.PAS contained in archive : VOL7N12.ZIP
PROGRAM SeekToTextDemo;

FUNCTION SeekToText(VAR TextFile : Text; OffSet : Real) : Integer;
TYPE {see the Turbo Pascal 3.X reference manual for the FIB layout}
FIBtype = RECORD
Handle, RecLength, BufOff, BufSize, BufPtr, BufEnd : Integer;
FilePath : ARRAY[1..64] OF Char;
END; {FIBtype}
VAR
ByteFile : FILE OF Byte ABSOLUTE TextFile;
FIB : FIBtype ABSOLUTE TextFile;
SaveRL : Integer;
BEGIN {SeekToText}
WITH FIB DO
BEGIN
SaveRL := RecLength; {RecLength actually holds flags and}
{maybe a char from the text file}
RecLength := 1; {A byte file "record" is one byte}
{$I-} LongSeek(ByteFile, OffSet); {$I+}
SeekToText := IOResult; {The caller must deal with IO errors}
RecLength := SaveRL; {restore values for the text file}
BufPtr := BufEnd; {force next Read/ReadLn to refill buffer}
END;
END; {PROCEDURE SeekToText}

VAR
DemoFile : Text;
i, j : Integer;
MaxLine : STRING[255];
CONST
DFOffsets : ARRAY[1..4] OF Real = (95, 0, 143, 43);
DFName = 'DEMOFILE.TXT';

BEGIN {SeekToTextDemo}
Assign(DemoFile, DFName);
{$I-} Reset(DemoFile); {$I-}
IF IOResult <> 0 THEN
BEGIN
WriteLn('Failed to open ', DFName);
Halt(IOResult);
END; {if IOResult <> 0}
FOR i := 1 TO 4 DO
BEGIN
j := SeekToText(DemoFile, DFOffsets[i]);
IF j <> 0 THEN
BEGIN
WriteLn('SeekToText failure with DFOffsets[', i, ']');
Halt(j);
END {j <> 0}
ELSE
BEGIN {j = 0}
ReadLn(DemoFile, MaxLine);
WriteLn(MaxLine);
END; {j = 0}
END; {for i := 1 to 4}
WriteLn;
{$I-} Close(DemoFile); {$I-}
IF IOResult <> 0 THEN
BEGIN
WriteLn('Failed to close ', DFName);
Halt(IOResult);
END; {if IOResult <> 0}
WriteLn('All operations concluded successfully.')
END.




  3 Responses to “Category : Files from Magazines
Archive   : VOL7N12.ZIP
Filename : SEEKTEXT.PAS

  1. Very nice! Thank you for this wonderful archive. I wonder why I found it only now. Long live the BBS file archives!

  2. This is so awesome! 😀 I’d be cool if you could download an entire archive of this at once, though.

  3. But one thing that puzzles me is the “mtswslnkmcjklsdlsbdmMICROSOFT” string. There is an article about it here. It is definitely worth a read: http://www.os2museum.com/wp/mtswslnk/