F$VERIFY()

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F$VERIFY is a lexical function that returns an integer value indicating whether the procedure verification setting is currently on or off. If used with arguments, the F$VERIFY function can turn the procedure and image verification settings on or off. You must include the parentheses after the F$VERIFY function whether or not you specify arguments.

Syntax

F$VERIFY([procedure-value] [,image-value])

Return Value

The integer 0 if the procedure verification setting is off, or the integer 1 if the procedure verification setting is on.

Arguments

procedure-value

Specifies an integer expression with a value of 1 to turn procedure verification on, or a value of 0 to turn procedure verification off. When procedure verification is on, each DCL command line in the command procedure is displayed on the output device. Procedure verification allows you to verify that each command is executing correctly. If you use the procedure-value argument, the function first returns the current procedure verification setting. Then the command interpreter turns the procedure verification on or off, as specified by the argument.

image-value

Specifies an integer expression with a value of 1 to turn image verification on, or a value of 0 to turn image verification off. When image verification is on, data lines in the command procedure are displayed on the output device.

Examples

$ SAVE_PROC_VERIFY = F$ENVIRONMENT("VERIFY_PROCEDURE") 
$ SAVE_IMAGE_VERIFY = F$ENVIRONMENT("VERIFY_IMAGE") 
$ SET NOVERIFY 
. . . 
$ TEMP = F$VERIFY(SAVE_PROC_VERIFY, SAVE_IMAGE_VERIFY) 

This example shows an excerpt from a command procedure. The first assignment statement assigns the current procedure verification setting to the symbol SAVE_PROC_VERIFY. The second assignment statement assigns the current image verification setting to the symbol SAVE_IMAGE_VERIFY. Then, the SET NOVERIFY command disables procedure and image verification. Later, the F$VERIFY function resets the verification settings, using the original values (equated to the symbols SAVE_PROC_VERIFY and SAVE_IMAGE_VERIFY). The symbol TEMP contains the procedure verification before it is changed with the F$VERIFY function. (In this example, the value of TEMP is not used.)

$ VERIFY = F$VERIFY() . . . 
$ IF VERIFY .EQ. 0 THEN SET VERIFY 

This example shows an excerpt from a command procedure that uses the F$VERIFY function to save the current procedure verification setting and to turn both procedure and image verification off. At the end of the command procedure, if procedure verification was originally on, both the procedure and image verification are turned on.