Category : Modula II Source Code
Archive   : M2TUTOR.ZIP
Filename : CH08E2.MOD

(* Chapter 8 - Programming exercise 2 *)
MODULE CH08E2;

FROM FileSystem IMPORT Lookup, Close, File, Response, ReadChar;
FROM InOut IMPORT Write, WriteString, WriteCard, ReadString,
WriteLn, EOL;

VAR NameOfFile : ARRAY[1..15] OF CHAR;
InFile : File;
InLine : ARRAY[1..80] OF CHAR; (* Note, There is no check
for a spill out of
this line. Assumes all
lines are shorter. *)
Character : CHAR;
Count : CARDINAL;
ENDCount : CARDINAL;

PROCEDURE CheckForEND;
VAR ENDFound : BOOLEAN;
Index : INTEGER;
BEGIN
ENDFound := FALSE;
FOR Index := 1 TO (INTEGER(Count) - 2) DO
IF (InLine[Index] = 'E') AND
(InLine[Index + 1] = 'N') AND
(InLine[Index + 2] = 'D') THEN
ENDFound := TRUE;
ENDCount := ENDCount + 1;
END;
END;

IF ENDFound THEN
WriteString(InLine);
WriteLn;
END;

END CheckForEND;

BEGIN
REPEAT (* repeat until a good filename is found *)
WriteLn;
WriteString("Enter name of file to display ---> ");
ReadString(NameOfFile);
Lookup(InFile,NameOfFile,FALSE);
UNTIL InFile.res = done; (* good filename found *)
ENDCount := 0;
WriteLn;
Count := 0;
InLine[1] := 0C; (* String terminator *)
REPEAT (* character read/display loop - quit at InFile.eof *)
ReadChar(InFile,Character);
IF NOT InFile.eof THEN
IF Character # EOL THEN
Count := Count + 1;
InLine[Count] := Character;
InLine[Count + 1] := 0C; (* String terminator *)
ELSE
CheckForEND;
Count := 0;
InLine[1] := 0C; (* String terminator *)
END;
END;
UNTIL InFile.eof; (* quit when eof is found *)
Close(InFile);

WriteLn;
WriteString("There were");
WriteCard(ENDCount,5);
WriteString(" END's in the file.");
WriteLn;
END CH08E2.




(* Result of execution

(The selected file is listed on the monitor, with the character
count listed for each line, and the total number of lines.)

*)