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X-Hacker.org- The Guide To Clipper - <b>errorlevel()</b>
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ERRORLEVEL()
Syntax: ERRORLEVEL([<expN>])
Purpose: To return the current Clipper exit code if one has been set
and optionally set the exit code to a new value.
Argument: <expN> is the new exit code setting. This can be a
value between zero and 65,535.
Returns: An integer numeric value.
ERRORLEVEL() returns the current Clipper exit code if one
has been set using ERRORLEVEL() with an argument; otherwise
it returns zero.
Usage: ERRORLEVEL() is primarily designed to use with SWITCH.EXE in
order to chain execution of application programs. As an
example, assume you have a main application program and,
depending on some condition, it needs to execute another
.EXE file. You can do this by setting the error level just
before exiting to DOS as follows:
IF choice = "ONE"
err_lev = 1
ELSEIF choice = "TWO"
err_lev = 2
ELSEIF choice = "THREE"
err_lev = 3
ENDIF
ERRORLEVEL(err_lev) && Set error level.
QUIT
You then execute SWITCH from the DOS prompt specifying the
list of executable application programs corresponding to
error levels specified in the shell program. For example:
C>SWITCH ONE TWO THREE
Notes: . ERRORLEVEL() is not updated when a child process
terminates. To obtain this information you must create an
assembler or C routine that queries the child process exit
code using INT 21 Function 4D.
Library: CLIPPER.LIB
----------------------------------- Example --------------------------------
error_level = ERRORLEVEL() && Get current error level.
ERRORLEVEL(1) && Set new error level.
See Also: CANCEL QUIT SWITCH.EXE
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