System Functions

ERR( )

Test Error Value

Formats

1.	Return ERR Position:	ERR(compare1,compare2,...[,ERR=stmtref])
2.	Return Extended Error Information:	ERR(keyword$ \| "*")
2a.	Return Extended Error History:	ERR(keyword$, occurrence)

Where:

(asterisk) Lists the names of the returned values.

compare1,
compare2, ...

Comma-separated list of numeric values for comparison with the value of the internal ERR variable.

keyword$

Currently supported return values:

Keyword	Value Returned
ERR	Error condition
RET	OS error
OSERR	OS error message; i.e. MSG(-1)
PROGRAM	Pathname of program with error
STNO	Statement number
OBJ	Object number
METHOD	Method name invoked
LFA	Last file accessed
LFO	Last file opened
LASTPATH	Last pathname referenced
LASTKEY	Record key value, only valid for Error 11s
*	Returns a list of all the possible ERR function keywords, comma-separated

occurrence

Error history occurrence where 1 is the last recorded error, 2 is the error before that, etc. Maximum value must be <= the value in the 'EH' system parameter. (added in PxPlus v10.10)

stmtref

Program line number or statement label to which to transfer control.

Description

The ERR( ) function can be used to determine the value of the internal ERR variable or receive additional information about the last un-trapped error.

Format 1

Return ERR Position

ERR(compare_1,compare_2,...compare_n[,ERR=stmtref])

Use this format to compare the value of the internal ERR variable with a list of possible external error values. If a match is found, the function returns an integer reporting the relative position of the value, which matches the value in the external ERR system variable. The function returns 0 (zero) if no match is found.

Example:

0040 on err(1,11,2) goto 1000,1010,1110,1020

Possible results:

	ERR=1	Control transfers to line 1010.
	ERR=11	Control transfers to line 1110.
	ERR=2	Control transfers to line 1020.
	ERR=0	No match. Control transfers to line 1000.

Format 2

Return Extended Error Information

ERR(keyword$ [,occurrence])

Where:

keyword$	Identifier of the error information you want returned.
occurrence	Option occurrence when accessing the error history, if enabled using the 'EH' system parameter. If omitted, the *default* error information from the last un-trapped exception is returned.

This format provides additional information for diagnosing un-trapped errors. The valid keywords vary from release to release. The currently supported keywords can be found by requesting ERR("*"), which will return a comma-delimited list of the keywords currently supplied. As of PxPlus 2018, this list contains:

Keyword	Description
ERR	Error code
ERX	Extended error code (Not Currently Used)
RET	OS error code
OSERR	OS error message
PROGRAM	Program that encountered error
ENTRYPOINT	Entry point where execution started in program
STNO	Statement/Line number where error occurred
OBJ	Object handle if error occurred in object
METHOD	Entry point if error occurred within an object method
LFA	Last file accessed
LFO	Last file opened
LASTPATH	Pathname of last file opened
LASTKEY	Last key used
MODULE	Internal PxPlus module that trapped error
LINE	Line in module

The information returned by the default ERR( ) function is not affected by errors that are programmatically trapped using a SETERR or any of the ERR=/DOM=/BSY= options.