EXIT

You can use EXIT when you need information from an existing function in a library or a program or when you need to use a general function that is not available.

Depending on the execution operating system, there are two different methods for the EXIT function: 1) the library method and 2) the program method. The program method is not supported on Windows operating systems.

Syntax:

EXIT (single-text-expression, single-text-expression,
single-text-expression)

Meaning:

1. EXIT (library_name, function_name, input_to_the_function)
2. EXIT ( program_name , command_line_arg1 , command_line_arg2 )

Returns:

A single text item

Meaning 1 - library method

At run time, the function_name function will execute in the library specified by library_name passing input_to_the_function as a text string. The result of function_name is returned as a text item by means of lpep- > lpdataFromApp.

Set lpep- > nReturn equal to 0 if the function is to succeed or set it equal to 1 to fail.

For detailed information about the requirements of the library function that is executed by the EXIT, see Implementing a library EXIT function.

To build this shared library, run the following commands:

cc -c share1.c

cc -o mcshex.so share1.o -bE:shrsub.exp -bM:SRE -eAIXEntry

Meaning 2 - program method

The program method of the EXIT function is not supported on Windows operating systems.

At execution time, the program specified by program_name executes and passes the concatenation of command_line_arg1 + " " + command_line_arg2 as a text string.

Whatever is returned by program_name to the standard output device is returned as text.

Examples

• EXIT ( program_name , command_line_arg1 , command_line_arg2 )

  Returns a text string from the function or application that is executed. If the EXIT function is not available for a particular operating system, EXIT returns none.

• EXIT ( "mydll.dll" , "myfunction" , "12" )

  This Windows library example passes the value 12 to myfunction, a function in mydll.dll. The value of the item returned depends on what myfunction does with the 12 passed to it.

• IF (EXIT ("mylib.sl" , "ckCust" , CustID Column:Row:DB) = "OK" , MapKnownCust ( Row:DB ) , MapUnknownCust ( Row:DB ) )

  Similarly, this UNIX library example passes the value of CustID Field to ckCust, a function in a UNIX shared library called mylib.sl. If the value returned by ckCust is OK, a functional map is called to map Row for a known customer. Otherwise, another functional map is executed to map Row for an unknown customer.

• EXIT ( "pwd" , " " , " " )

  This UNIX program example executes the UNIX print working directory (pwd) command to determine the current directory. The name of the current working directory is then returned as a text string. Notice that although the pwd command does not require additional command line arguments, command_line_arg1 and command_line_arg2 must be included as a space enclosed in double quotation marks (" ").

• TEXTTONUMBER ( ( EXIT ( "GetIncome" , Applicant:Form , "*Mortgage" ) )

  This program example passes the value of Applicant concatenated to the text literal *Mortgage to an application called GetIncome. The result is converted to a number.

Related functions

• DDEQUERY
• FAIL
• GET
• LASTERRORCODE
• LASTERRORMSG
• PUT
• RUN
• VALID