ECHO

Operation Notes

Displays its argument, message, on the standard list device ($STDLIST). The command ignores delimiters. Quotation marks are not required around message. The ECHO command does not perform dereferencing of any kind. If you want variable dereferencing you must use explicit dereferencing (!) in the argument. A null message ( Return ) displays a linefeed.

The ECHO command is not suppressed by OPTION NOLIST in a UDC or command file, or by any setting of the HPMSGLEVEL variable.

Use

This command is available in a session, job, program, or in BREAK. Pressing Break has no effect on this command.

Examples

In the following example, although there is a variable named a that has a string value, ECHO simply displays the character a because no dereferencing has been specified.

 SETVAR a, 'hi there'
 
 ECHO a
 a

This time ECHO is given the value of the variable a argument. Explicit dereferencing has been specified and the dereferencing is done before ECHO is executed.

 ECHO !a
 hi there

Two exclamation points are resolved to one exclamation point by string substitution, and MPE/iX is prohibited from making the value substitution (even number rule).

 ECHO a
 !a

Triple (or any odd number of) exclamation points treat the argument as !a, which resolves to ! and !a, giving !hi there (odd number rule).

 ECHO !a
 !hi there

If you entered the following command line in a user command, you would see a message when an error occurred:

 IF CIERROR <> 0 THEN
 ECHO ** A CIERROR OCCURRED!: (CIERR !CIERROR) **

The first instance of CIERROR has no dereferencing, and so ECHO treats it literally. The second instance, !CIERROR, contains explicit dereferencing, and so MPE/iX substitutes a value for the system variable CIERROR before the message is displayed to $STDLIST. So, for example, if the program generated error 975, you would see this message:

 ** A CIERROR OCCURRED!: (CIERR 975) **