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{{fbdoc item="title" value="ERR"}}----
Get or set the run-time error number

{{fbdoc item="usage"}}##
//result// = **Err**( )
//or//
**Err** = //number//
##
{{fbdoc item="desc"}}
The ##**Err()**## function returns the ""FreeBASIC"" run-time error number (a 32 bit ##[[KeyPgLong|Long]]##) which can be set by the built-in statements and functions, or by the program through ##**Err = //number//**## or ##[[KeyPgError|Error]]##. Unlike ##[[KeyPgError|Error]]##, ##**Err = //number//**## sets the error number without invoking an error handler.

See [[TblRuntimeErrors|Runtime Error Codes]] for a listing of the predefined runtime error numbers and their associated meaning. The program may use additional custom error numbers.

##**Err**## can always be used, even if QB-like error handling is not enabled. ##**Err**## is reset by ##[[KeyPgResume|Resume]]## and ##[[KeyPgResumenext|Resume Next]]##.

Note: Care should be taken when calling an internal function (such as ##[[KeyPgPrint|Print]]##) after an error occurred, because it will reset the error value with its own error status. To preserve the ##**Err**## value, it is a good idea to store it in a variable as soon as the error handler is entered.

Remark: Some procedures used in their function version return directly the error code (a 32 bit ##[[KeyPgLong|Long]]##).
That is the case for: ##[[KeyPgBload|Bload]]##, ##[[KeyPgBsave|Bsave]]##, ##[[KeyPgClose|Close]]##, ##[[KeyPgFilecopy|FileCopy]]##, ##[[KeyPgGetjoystick|GetJoystick]]##, ##[[KeyPgGetmouse|GetMouse]]##, ##[[KeyPgImageInfo|ImageInfo]]##, ##[[KeyPgKill|Kill]]##, ##[[KeyPgOpen|Open]]##, ##[[KeyPgOpenCom|Open Com]]##, ##[[KeyPgOpenCons|Open Cons]]##, ##[[KeyPgOpenErr|Open Err]]##, ##[[KeyPgOpenLpt|Open Lpt]]##, ##[[KeyPgOpenPipe|Open Pipe]]##, ##[[KeyPgOpenScrn|Open Scrn]]##, ##[[KeyPgScreenres|ScreenRes]]##, ##[[KeyPgScreensync|ScreenSync]]##, ##[[KeyPgSetdate|SetDate]]##, ##[[KeyPgSetmouse|SetMouse]]##, ##[[KeyPgSettime|SetTime]]##.

{{fbdoc item="ex"}}
An example using QBasic style error handling (compile with -ex option)
{{fbdoc item="filename" value="examples/manual/error/err1.bas"}}%%(freebasic)
'' Compile with -lang fblite or qb

#lang "fblite"

On Error Goto Error_Handler
Error 150
End

Error_Handler:
n = Err()
Print "Error #"; n
Resume Next
%%
An example using inline error handling (note: ##[[KeyPgOpen|Open]]## can also return its own error status when called as a function)
{{fbdoc item="filename" value="examples/manual/error/err2.bas"}}%%(freebasic)
'' compile without -e switch

dim filename as string

do
line input "Input filename: ", filename
if filename = "" then end
open filename for input as #1
loop until err() = 0

print using "File '&' opened successfully"; filename
close #1
%%

{{fbdoc item="diff"}}
- Error numbers are not the same as in QB.

{{fbdoc item="see"}}
- ##[[KeyPgOnerror|On Error]]##
- ##[[KeyPgError|Error]]##
- [[ProPgErrorHandling|Error Handling]]
- [[TblRuntimeErrors|Runtime Error Codes]]

{{fbdoc item="back" value="CatPgError|Error Handling Functions"}}
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