| Navigation: Language Reference > 13 - Built-in Functions >====== PUSHERRORS (write error information) ====== |    |
PUSHERRORS( )
| PUSHERRORS | Writes the last error information to an internal memory stack. |
The PUSHERRORS procedure writes the current error states of the current thread's ERRORCODE(), ERROR(), FILEERRORCODE(), FILEERROR(), ERRORFILE(), the C library errno variable, and the current Windows error code returned by the GetLastError() API function.
POPERRORS is used to restore the error states originally saved by PUSHERRORS. The main purpose of these functions is to save errors states and then check them later, after performing some additional code that can potentially change them.
PUSHERRORS and POPERRORS works using the LIFO (last in, first out) stack convention. The maximum depth of the stack is dependent on available memory. Because ERRORCODE(), ERROR(), etc. are thread dependent, PUSHERRORS and POPERRORS statements that are called from different threads are independent of each other, and allocate a different memory stack for each thread.
Example:
PROGRAM
MAP
InitialErrors()
END
TESTFILE FILE,DRIVER('DOS')
RECORD
f1 BYTE
END
END
CODE
!file processing and initialization here
OPEN(testfile) !forcing an error
PUSHERRORS()
!additional code here
InitialErrors
InitialErrors PROCEDURE
ERRORCODEVAR LONG
ERRORVAR CSTRING(255)
FILEERRORCODEVAR LONG
FILEERRORVAR CSTRING(255)
ERRORFILEVAR CSTRING(255)
Window WINDOW('Error Report'),AT(,,362,128),FONT('MS Sans Serif',8,,FONT:regular,CHARSET:ANSI),SYSTEM, |
GRAY
PROMPT('ERRORCODE:'),AT(9,10),USE(?Prompt1)
STRING(@N_4),AT(97,10,43,10),USE(ERRORCODEVAR)
PROMPT('ERROR:'),AT(9,25),USE(?Prompt2)
STRING(@s40),AT(96,25),USE(ERRORVAR)
PROMPT('FILEERRORCODE:'),AT(9,40),USE(?Prompt3)
STRING(@N_4),AT(95,40),USE(FILEERRORCODEVAR)
PROMPT('FILEERROR:'),AT(9,55),USE(?Prompt4)
STRING(@S40),AT(95,55),USE(FILEERRORVAR)
PROMPT('ERRORFILE:'),AT(9,70),USE(?Prompt5)
STRING(@S40),AT(95,71),USE(ERRORFILEVAR)
END
CODE
POPERRORS()
ERRORCODEVAR = ERRORCODE() !will return 2
ERRORVAR = ERROR() !will return “File Not Found”
FILEERRORCODEVAR = FILEERRORCODE()
FILEERRORVAR = FILEERRORCODE()
ERRORFILEVAR = ERRORFILE() !will return “TESTFILE”
OPEN(WINDOW)
ACCEPT
DISPLAY
END
See Also: