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systemErrorCode% = SYSERROR
This function returns the value of the
SYSERROR variable, which is an internal variable that FB uses to store the MacOS result codes from disk i/o operations.
SYSERROR usually returns toolbox result codes, it also returns three error codes that are unique to FB. These are:
Example: -9999 The file number used was outside of the legal range. Example: OPEN "I",#-1000-8888 The program attempted to open a file using a file number that was already in use. Example: OPEN "R",#1,"Test" OPEN "R",#1,"Something Else" -6666 An illegal open type was used. Example: OPEN "XYZ",#1,"Test"
SYSERROR statement; ERROR function; ON ERROR