Im having problems with this code, I have two file of char, one is filed with information about books, and the other is empty, i have to write in SAL some information from S and then show the total of how many books match the first 2 digits of the code and how many are R and how many are T. The code, does write the information form S to Sal, but when its supposed to show the totals it appears ERORR 100 on screen. I read about it and it says that it is a problem with 'Disk read error' and that *This error typically occurs, if you "seed" a non-existent record of a typed file and try to read/write it. *, i really dont undertand.
I've benn trying to figure it out, but I haven't been able to. I notice that if I dont put 'WHILE NOT EOF(S) DO' the error does not appear, but of course i need the while, if someone is able to point out my mistakes i would really apreciate it.
This is the code:
uses crt;
var
i : byte;
s,sal: file of char;
v,l1,l2: char;
cs,cn,cl: integer;
pn,ps,tot: integer;
BEGIN
cs:=0; cn:=0; i:=0; cl:=0;
Assign (s, 'C:\Users\te\Documents\s.txt');
{$I-}
Reset (s);
{$I+}
if IOResult <> 0 then
begin
writeln('Error');
halt(2);
end;
Assign (sal, 'C:\Users\te\Documents\sal.txt');
{$I-}
Rewrite (sal);
IOResult;
{$I+}
if IOResult <> 0 then
halt(2);
writeln('Please write the code of the book, only 2 digits');
read(L1);read(L2);
read(s,v);
while (not eof(s)) do
begin
for i:=1 to 2 do
read(s,v);
if (v = '0') then
begin
read(s,v);
if (v = '1') or (v = '2') then
begin
for i:=1 to 5 do
read(s,v);
if (v = 'R') then
begin
read(s,v);
cs:= cs + 1;
end
else
begin
if (v = 'T') then
begin
cn:= cn + 1;
read(s,v);
end;
end;
while (v <> '-') do
read(s,v);
while (v = '-') do
read(s,v);
if (v = L1) then
begin
write(sal, v);
read(s,v);
if (v = L2) then
begin
write(sal,v);
read(s,v);
cl:= cl + 1;
end;
end;
while ( v <> '/') do
begin
write(sal,v);
read(s,v);
end;
write(sal, '-');
end
else
begin
for i:= 1 to 5 do
read(s,v);
if (v = 'R') then
cs:= cs + 1
else
cn:= cn + 1;
if (v = L1) then
read(s,v);
if (v = L2) then
begin
cl:= cl + 1;
read(s,v);
end;
end;
end
else
begin
for i:= 1 to 5 do
read(s,v);
if (v = 'R') then
cs:= cs + 1
else
cn:= cn + 1;
if (v = L1) then
read(s,v);
if (v = L2) then
begin
cl:= cl + 1;
read(s,v);
end;
end;
end;
tot:= cs + cn;
ps:= (cs * 100) div tot;
pn:= (cn * 100) div tot;
writeln('TOTAL ',cl);
writeln();
writeln(ps,'% and',pn,'%');
The file S content:
02022013Rto kill a mockingbird-1301/02012014Tpeter pan-1001/02032013Thowto-2301/02012012Tmaze runner-1001/02012012Tmaze runner-1001/02012012Tmaze runner-1001/$
I really just need someone else's point of view on this code, I think maybe the algorithm is flawed.
Thanks
(After your edit, i see that your code now compiles w/o error in FPC, so I'm glad you've managed to fix the error yourself)
As this is obviously coursework, I'm not going to fix your code for you and in any case the wayEven so, I'm afraid you are going about this is completely wrong.
Basically, the main thing wrong with your code is that you are trying to control what happens as your read the source file character by character. Quite frankly, that's a hopeless way of trying to do it, because it makes the execution flow unnecessarily complicated and littered with ifs, buts and loops. It also requires you to keep mental track of what you are trying to do at any given step, and the resulting code is inherently not self-documenting - imagine if you came back to your code in six months, could you tell at a glance how it works and what it does? I certsinly couldn't personally.
You need to break the task down in a different way. Instead of analysing the problem from the bottom up ("If I read this character next, then what I need to do next is ...') do it from the top down: Although your input file is a file of char, it contains a series of strings, separated by a / character and finally terminated by a $ (but this terminator does not really matter). So what you need to do is to read these strings one-by-one; once you've got one, check whether it's the one you're looking for: if it is. process it however you need to, otherwise read the next one until you reach the end of the file.
Once you have successfully read one of the book strings, you can then split it up into the various fields it's composed of. The most useful function for doing this splitting is probably Copy, which lets you extract substrings from a string - look it up in the FPC help. I've included functions ExtractTitle and ExtractPreamble which show you what you need to do to write similar functions to extract the T/R code and the numeric code which follows the hyphen. Btw, if you need to ask a similar q in the future, it would be very helpful if you include a description of the layout and meaning of the various fields in the file.
So, what I'm going to show you is how to read the series of strings in your S.Txt by building them character-by-character. In the code below, I do this using a function GetNextBook which I hope is reasonable self-explanatory. The code uses this function in a while loop to fill the BookRecord string variable. Then, it simply writes the BookRecord to the console. What your code should do, of course, is to process the BookRecord contents to see if it is the one you are looking for and then do whether the remainder of your task is.
I hope you will agree that the code below is a lot clearer, a lot shorter and will be a lot easier to extend in future than the code in your q. They key to structuring a program this way is to break the program's task into a series of functions and procedures which each perform a single sub-task. Writing the program that way makes it easier to "re-wire" the program to change what it does, without having to rewrite the innards of the functions/procedures.
program fileofcharproject;
uses crt;
const
sContents = '02022013Rto kill a mockingbird-1301/02012014Tpeter pan-1001/02032013Thowto-2301/02012012Tmaze runner-1001/02012012Tmaze runner-1001/02012012Tmaze runner-1001/$';
InputFileName = 'C:\Users\MA\Documents\S.Txt';
OutputFileName = 'C:\Users\MA\Documents\Sal.Txt';
type
CharFile = File of Char; // this is to permit a file of char to be used
// as a parameter to a function/procedure
function GetNextBook(var S : CharFile) : String;
var
InputChar : Char;
begin
Result := '';
InputChar := Chr(0);
while not Eof(S) do begin
Read(S, InputChar);
// next, check that the char we've read is not a '/'
// if it is a '/' then exit this while loop
if (InputChar <> '/') then
Result := Result + InputChar
else
Break;
end;
end;
function ExtractBookTitle(BookRecord : String) : String;
var
p : Integer;
begin
Result := Copy(BookRecord, 10, Length(BookRecord));
p := Pos('-', Result);
if p > 0 then
Result := Copy(Result, 1, p - 1);
end;
procedure AddToOutputFile(var OutputFile : CharFile; BookRecord : String);
var
i : Integer;
begin
for i := 1 to Length(BookRecord) do
write(OutputFile, BookRecord[i]);
write(OutputFile, '/');
end;
function ExtractPreamble(BookRecord : String) : String;
begin
Result := Copy(BookRecord, 1, 8);
end;
function TitleMatches(PartialTitle, BookRecord : String) : Boolean;
begin
Result := Pos(PartialTitle, ExtractBookTitle(BookRecord)) > 0;
end;
var
i : Integer; //byte;
s,sal: file of char;
l1,l2: char;
InputChar : Char;
BookFound : Boolean;
cs,cn,cl: integer;
pn,ps,tot: integer;
Contents : String;
BookRecord : String;
PartialTitle : String;
begin
// First, create S.Txt so we don't have to make any assumptions about
// its contents
Contents := sContents;
Assign(s, InputFileName);
Rewrite(s);
for i := 1 to Length(Contents) do begin
write(s, Contents[i]); // writes the i'th character of Contents to the file
end;
Close(s);
cs:=0; cn:=0; i:=0; cl:=0;
// Open the input file
Assign (s, InputFileName);
{$I-}
Reset (s);
{$I+}
if IOResult <> 0 then
begin
writeln('Error');
halt(2);
end;
// Open the output file
Assign (sal, OutputFileName);
{$I-}
Rewrite (sal);
IOResult;
{$I+}
if IOResult <> 0 then
halt(2);
// the following reads the BookRecords one-by-one and copies
// any of them which match the partial title to sal.txt
writeln('Enter part of a book title, followed by [Enter]');
readln(PartialTitle);
while not Eof(s) do begin
BookRecord := GetNextBook(S);
writeln(BookRecord);
writeln('Preamble : ', ExtractPreamble(BookRecord));
writeln('Title : ', ExtractBookTitle(BookRecord));
if TitleMatches(PartialTitle, BookRecord) then
AddToOutputFile(sal, BookRecord);
end;
// add file '$' to sal.txt
write(sal, '$');
Close(sal);
Close(s);
writeln('Done, press any key');
readln;
end.
How can I add a line to a file/template before a specific other line, if it doesn't exist?
For example for the following JS file, I have to make sure that there's dependencies.push(...) line between the ABOVE THIS LINE and BELOW THIS LINE comment-lines. If the dependencies.push(...) is not present, I have to add it before the BELOW THIS LINE comment-line:
(function(ng) {
var dependencies = [];
/*DO NOT MODIFY ABOVE THIS LINE!*/
dependencies.push("mxdfNewTransaction.controller.mxdfNewTransactionCtrl");
/*DO NOT MODIFY BELOW THIS LINE!*/
ng.module('prismApp.customizations', dependencies, null);
})(angular);
I have to also do the same thing with a similar HTML template file.
Thanks for your help.
You have to parse the file line-by-line to find the spot to insert your code.
Something like this:
function AddLineToTemplate(
FileName: string; StartLine, EndLine, AddLine: string): Boolean;
var
Lines: TArrayOfString;
Count, I, I2: Integer;
Line: string;
State: Integer;
begin
Result := True;
if not LoadStringsFromFile(FileName, Lines) then
begin
Log(Format('Error reading %s', [FileName]));
Result := False;
end
else
begin
State := 0;
Count := GetArrayLength(Lines);
for I := 0 to Count - 1 do
begin
Line := Trim(Lines[I]);
if (CompareText(Line, StartLine) = 0) then
begin
State := 1;
Log(Format('Start line found at %d', [I]));
end
else
if (State = 1) and (CompareText(Line, AddLine) = 0) then
begin
Log(Format('Line already present at %d', [I]));
State := 2;
break;
end
else
if (State = 1) and (CompareText(Line, EndLine) = 0) then
begin
Log(Format('End line found at %d, inserting', [I]));
SetArrayLength(Lines, Count + 1);
for I2 := Count - 1 downto I do
Lines[I2 + 1] := Lines[I2];
Lines[I] := AddLine;
State := 2;
if not SaveStringsToFile(FileName, Lines, False) then
begin
Log(Format('Error writing %s', [FileName]));
Result := False;
end
else
begin
Log(Format('Modifications saved to %s', [FileName]));
end;
break;
end;
end;
if Result and (State <> 2) then
begin
Log(Format('Spot to insert line was not found in %s', [FileName]));
Result := False;
end;
end;
end;
You can use it like this:
if AddLineToTemplate(
'C:\path\to\customizations.js',
'/*DO NOT MODIFY ABOVE THIS LINE!*/',
'/*DO NOT MODIFY BELOW THIS LINE!*/',
' dependencies.push("mxdfNewTransaction.controller.mxdfNewTransactionCtrl");') then
begin
Log('Success');
end
else
begin
Log('Failure');
end;
Beware of the LoadStringsFromFile and SaveStringsToFile limitations, when working with Unicode files. See Inno Setup Reading file in Ansi and Unicode encoding.
I am attempting to write a comment stripper in pascal. I run my code and pass it a C source code file and it strips the comments from the file and prints the result to terminal.
I am fairly new to pascal. I am getting some very strange output and I cannot figure out why. The code checks for comments line by line and prints characters one at a time. The comment stripper is printing what seems to be random characters whenever it reaches the start of a new line. I am using pascals Write(Str[i]) function to print characters and WriteLn() once the end of a line is reached.
I have no idea why im receiving weird output. I am running Linux Mint and can compile and run my code, but I receive this strange output. I also tried running my code on a Mac and received a run-time error:
Program Path: ./Assignment1
File Name: lol.c
Runtime error 2 at $00011532
$00011532
$0002F7F6
$000113FD
$00011328
$00000002
Here is my code
program Assignment1;
uses
Sysutils;
var UserFile : TextFile;
TString : String;
OLine : String;
i : integer;
isComment : boolean;
skip : boolean;
begin
{$I+}
WriteLn('Program Path: ', ParamStr(0));
WriteLn('File Name: ', ParamStr(1));
Assign(UserFile, ParamStr(1) + '.c');
Reset(UserFile);
isComment := false;
skip := true;
Repeat
Readln(UserFile, TString);
for i:= 0 to ((Length(TString) - 1)) do
begin
if(skip) then
begin
skip := false;
continue;
end;
if(isComment = false) Then
begin
if(TString[i] = '/') Then
begin
if(TString[i+1] = '/') Then
begin
break;
end
else if(TString[i+1] = '*') Then
begin
isComment := true;
skip := true;
continue;
end;
end;
Write(TString[i]);
if(i = Length(TString) - 1) Then
begin
Write(TString[i + 1]);
end;
end
else
begin
if(TString[i] = '*') Then
begin
if(TString[i + 1] = '/') Then
begin
isComment := false;
skip := true;
continue;
end;
end;
end;
end;
WriteLn();
Until Eof(UserFile);
end.
I receive random characters which range from standard keyboard symbols to unicode blocks such as the ones found here.
Does anyone have any suggestions?
As 500 - Internal Server Error says, Pascal strings are 1-based. Your references to slot zero are returning garbage. If these are 256-byte strings you're getting the length code, I don't recall the memory layout of the pointer-based strings to know what you're getting in that case. You're also losing the last character of every string because of this.
Beyond that I see a definite bug: Look at what happens with a line ending in /
I also do not understand this:
if(i = Length(TString) - 1) Then
begin
Write(TString[i + 1]);
end;
It seems to me it's writing an extra character but I'm not sure.
I have problems with my pascal code.
When compiling it shows me the error: syntax : until expected but end found.
PROGRAM EvilGOTO;
Var rand,count,guess : integer;
LABEL correct, schleife, wrong, ende;
begin
Randomize;
count :=0;
repeat
schleife:
count := count+1;
rand := Random(10);
guess := Random(10);
if rand=guess
then
writeln('Correct')
end
else
writeln('False Guess')
goto schleife
until
count = 10;
end.
can you help me?
PROGRAM EvilGOTO;
Var rand,count,guess : integer;
begin
Randomize;
count :=0;
repeat
rand := Random(10);
guess := Random(10);
if rand=guess then
writeln('Correct')
else
begin
count := count+1;
writeln('False Guess');
end
until count = 10 or rand=guess;
end.
I have developed a TSP to talk to a CTI server. In the most part it works, but when setting the caller/called ID parties, in
function TSPI_lineGetCallInfo(
hdCall : HDRVCALL;
lpCallInfo : LPLINECALLINFO
) : LONG;
I am finding the offsets are all corrects but the size fields are NOT. At the end of the function I output (to debugger) the size and offsets of each field and they are what I expect them to be. But when I inspect the values using a TAPI program the sizes are different, (but the offsets are EXACTLY the same as per the debug statements) in fact the size field 5 regardless of what is actually there, whereas the debug statements at the end of the code below shows the correct values...
Any help greatly appreciated.
lpCallInfo^.dwCallerIDOffset := 0;
lpCallInfo^.dwCallerIDSize := 0;
lpCallInfo^.dwCalledIDOffset := 0;
lpCallInfo^.dwCalledIDSize := 0;
lpCallInfo^.dwConnectedIDOffset := 0;
lpCallInfo^.dwConnectedIDSize := 0;
extnid := thiscall.CallItem.ExtnId;
phoneno := thiscall.CallItem.DialNum;
extnid_size := (Length(extnid) + 1) * sizeof(WCHAR);
phoneno_size := (Length(phoneno) + 1) * sizeof(WCHAR);
extnidw := StringToWideStringEx(extnid, CP_ACP);
phonenow := StringToWideStringEx(phoneno, CP_ACP);
if lpCallInfo^.dwOrigin = LINECALLORIGIN_INTERNAL then
begin
{me}
lpCallInfo^.dwCallerIDOffset := sizeof(TLINECALLINFO);
lpCallInfo^.dwCallerIDSize := extnid_size;
Move(ExtnIdw[1], ptr^, extnid_size * 2);
ptr := Pointer(integer(ptr) + lpCallInfo^.dwCallerIDSize);
{other party}
if phoneno <> '' then
begin
lpCallInfo^.dwCalledIDOffset :=
sizeof(TLINECALLINFO) + lpCallInfo^.dwCallerIDSize;
lpCallInfo^.dwCalledIDSize := phoneno_size;
Move(phonenow[1], ptr^, phoneno_size * 2);
end;
end
else
begin
if thiscall.CallItem.CallType = 1 then
begin {incoming call}
{agent is the called party}
lpCallInfo^.dwCalledIDOffset := sizeof(TLINECALLINFO);
lpCallInfo^.dwCalledIDSize := extnid_size;
Move(ExtnIdw[1], ptr^, extnid_size);
ptr := Pointer(integer(ptr) + lpCallInfo^.dwCalledIDSize);
{other party is the caller}
if phoneno <> '' then
begin
lpCallInfo^.dwCallerIDOffset :=
sizeof(TLINECALLINFO) + lpCallInfo^.dwCalledIDSize;
lpCallInfo^.dwCallerIDSize := phoneno_size;
Move(phonenow[1], ptr^, phoneno_size);
ptr := Pointer(integer(ptr) + lpCallInfo^.dwCallerIDSize);
end;
end
else
begin
{agnet is the caller}
lpCallInfo^.dwCallerIDOffset := sizeof(TLINECALLINFO);
lpCallInfo^.dwCallerIDSize := extnid_size;
Move(ExtnIdw[1], ptr^, extnid_size);
ptr := Pointer(integer(ptr) + lpCallInfo^.dwCallerIDSize);
{dialed number is the called party}
if phoneno <> '' then
begin
lpCallInfo^.dwCalledIDOffset :=
sizeof(TLINECALLINFO) + lpCallInfo^.dwCallerIDSize;
lpCallInfo^.dwCalledIDSize := phoneno_size;
Move(phonenow[1], ptr^, phoneno_size);
ptr := Pointer(integer(ptr) + lpCallInfo^.dwCalledIDSize);
end;
end;
if (thiscall.CallItem.CallState = cs_Connected) and
(phoneno <> '') then
begin
lpCallInfo^.dwConnectedIDOffset := sizeof(TLINECALLINFO) +
lpCallInfo^.dwCallerIDSize + lpCallInfo^.dwCalledIDSize;
lpCallInfo^.dwConnectedIDSize := phoneno_size;
Move(phonenow[1], ptr^, phoneno_size);
ptr := Pointer(integer(ptr) + lpCallInfo^.dwConnectedIDSize);
end;
end;
end;
DEBUG('TSPI_lineGetCallInfo::dwCallerIDOffset=' + intToStr(lpCallInfo^.dwCallerIDOffset));
DEBUG('TSPI_lineGetCallInfo::dwCallerIDSize=' + intToStr(lpCallInfo^.dwCallerIDSize));
DEBUG('TSPI_lineGetCallInfo::dwCalledIDOffset=' + intToStr(lpCallInfo^.dwCalledIDOffset));
DEBUG('TSPI_lineGetCallInfo::dwCalledIDSize=' + intToStr(lpCallInfo^.dwCalledIDSize));
DEBUG('TSPI_lineGetCallInfo::dwConnectedIDOffset=' + intToStr(lpCallInfo^.dwConnectedIDOffset));
DEBUG('TSPI_lineGetCallInfo::dwConnectedIDSize=' + intToStr(lpCallInfo^.dwConnectedIDSize));
These are strange results. Your code seems to check out. It may be a longshot but the result could be caused by too few memory reserved for the lpCallInfo structure. What tapi program do you use? Most programs just reserve a large surplus beforehand. However, another commonly used approach is to 'ask' the TSP the exact amount needed by first calling TSPI_lineGetCallInfo and then reserving the exact amount after you set the dwNeededSize and returning LINEERR_STRUCTURETOOSMALL. You don't seem to check the dwTotalSize or set the dwNeededSize and dwUsedSize fields (which is dangerous).
Please look at the : LINEERR constants
and let me know if it solves the issue. If it doesn't, I would be curious to see the structure log from the Tapi Browser, but let's hope it works. Good luck!