System.IOResult

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Object Pascal

function IOResult: Integer;

C++

extern DELPHI_PACKAGE int __fastcall IOResult(void);

Properties

Type Visibility Source Unit Parent
function public
System.pas
System.hpp
System System

Description

Returns the status of the last I/O operation performed.

IOResult returns the result of the last Object Pascal I/O routine when I/O-checking is off (that is, when using the {$I-} compiler option). If IOResult returns 0, the last I/O operation succeeded. Otherwise, IOResult returns an error code.

If an I/O error occurs and I/O-checking is off, all subsequent I/O operations are ignored until the internal error flag is cleared. Calling IOResult clears the internal error flag.

An alternative way to handle I/O errors is to use exception handling with the {$I+} compiler option.

The following table lists all I/O errors, numbers, and descriptions.



Number

Name

Description

100

Disk read error

Reported by Read on a typed file if you attempt to read past the end of the file.

101

Disk write error

Reported by CloseFile, Write, WriteIn, or Flush if the disk becomes full.

102

File not assigned

Reported by Reset, Rewrite, Append, Rename, or Erase if the file variable has not been assigned a name through a call to Assign or AssignFile.

103

File not open

Reported by CloseFile, Read Write, Seek, Eof, FilePos, FileSize, Flush, BlockRead, or BlockWrite if the file is not open.

104

File not open for input

Reported by Read, Readln, Eof, Eoln, SeekEof, or SeekEoln on a text file if the file is not open for input.

105

File not open for output

Reported by Write or Writeln on a text file if you do not generate a Console application.

106

Invalid numeric format

Reported by Read or Readln if a numeric value read from a text file does not conform to the proper numeric format.



See Also


Code Examples