DOSERROR()
 Return the last DOS error number
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 Syntax

     DOSERROR([<nNewOsCode>]) --> nOsCode

 Arguments

     <nNewOsCode>, if specified, alters the value returned by DOSERROR().
     The value must be a numeric value that reflects a DOS error number.

 Returns

     DOSERROR() returns the DOS error number as an integer numeric value.

 Description

     DOSERROR() is an error function that returns the last DOS error code
     associated with an activation of the runtime error block.  When a
     runtime error occurs, the DOSERROR() function is set to the current DOS
     error if the operation has an associated DOS error.  The function value
     is retained until another runtime error occurs.  If the failed operation
     has no associated DOS error, the DOSERROR() returns zero.  With low-
     level file functions, FERROR() returns the same value as DOSERROR().

     Through use of the optional <nNewOsCode>, you may customize to the
     reporting activation the returned value for any DOS error.

     For a complete list of DOS error numbers and accompanying descriptions,
     refer to the Error Messages and Appendices Guide.

 Files   Library is CLIPPER.LIB.