Path: utzoo!mnetor!uunet!husc6!mit-eddie!uw-beaver!uw-june!uw-entropy!dataio!suvax1!hirayama
From: hirayama@suvax1.UUCP (Pat Hirayama)
Newsgroups: comp.lang.pascal
Subject: Re:  TurboP ErrorLevel return question
Message-ID: <869@suvax1.UUCP>
Date: 3 Jan 88 08:14:52 GMT
References: <11028@brl-adm.ARPA>
Organization: Seattle University, Seattle, WA.
Lines: 65

in article <11028@brl-adm.ARPA>, kirsch@braggvax.arpa (David Kirschbaum) says:
> 
> Richard asks how to return an ERRORLEVEL value from Turbo Pascal 3.0.
> Haven't actually tested this, but the manual (p135) on the Procedure Halt says:
> 
> "In PC/MSDOS, Halt may optionally pass a (sic) integer parameter specifying
> the return code of the program.  Halt without a parameter corresponds
> to Halt(0).  The return code may be examined by the parent process us-
> ing an MS-DOS system function call or through an ERRORLEVEL test
> in an MS-DOS batch file."


In TP4.0, the manual (p. 430) states the following about Halt:

Function	Stops program execution and returns to the operating system.
Declaration	Halt [ ( exitcode: word ) ]
Remarks		*exitcode* is an optional expression of type word that
		specifies the exit code of the program.  *Halt* without a 
		parameter corresponds to Halt(0).  The exit code can be 
		examined by a parent process using the DosExitCode function 
		in the Dos unit or through an ERRORLEVEL test in a DOS
		batch file.

		Note that *Halt* will initiate execution of any unit *Exit*
		procedures.

Also in TP4.0 manual (p.393):

DosExitCode function
Function	Returns the exit code of a subprocess.
Declaration	DosExitCode
Result Type	word
Remarks		The low byte is the code sent by the terminating process.
		The high byte is 0 for normal termination, 1 if terminated
		by Ctrl-C, 2 if terminated due to a device error, or 3
		if terminated by the Keep procedure.

Also in TP4.0 manual (p.438):

Keep procedure
Function	Keep (or Terminate Stay Resident) terminates the program
		and makes it stay in memory.
Declaration	Keep(ExitCode: word)
Remarks		The entire program stays in memory--including data segment,
		stack segment, and heap--so be sure to specify a maximum size
		for the heap using the $M compiler directive.  The *ExitCode*
		corresponds to the one passed to the *Halt* standard procedure.
Restrictions	Use with care!  Terminate Stay Resident (TSR) programs are
		complex and *no* other support for them is provided.  Refer
		to the MS-DOS technical documentation for more information.


I hope that some of this helps.


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