READT

READT statement is used to read a range of tape devices 0-9.

COMMAND SYNTAX

    READT variable { FROM expression } THEN | ELSE statements

SYNTAX ELEMENTS

variable is the variable that will receive any data read from the tape device.

expression should evaluate to an integer value in the range 0-9 and specifies from which tape channel to read data. If the FROM clause is not specified the READT will assume channel 0.

If the READT fails then the statements associated with any ELSE clause will be executed. SYSTEM (0) will return the reason for the failure as follows:

NOTES

A "tape" does not only refer to magnetic tape devices, but also any device that has been described to TAFC. Writing device descriptors for jBASE is beyond the scope of this manual.

If no tape device has been assigned to the specified channel the TAFC debugger is entered with an appropriate message.

Each instance of the READT statement will read the next record available on the device. The record size is not limited to a single tape block and the entire record will be returned whatever block size has been allocated by the T-ATT command.

EXAMPLE

    LOOP
    	  READT TapeRec FROM 5 ELSE
        	  Reason = SYSTEM(0)
        	  IF Reason = 2 THEN BREAK ;* done
        	  CRT "ERROR"  ;  STOP
    	  END
    REPEAT