Programming instructions

Intermec Fingerprint v7.61 – Programmer’s Reference Manual Ed. 7158
Chapter 2 Program Instructions
LOF
Field of Application Function returning the length in bytes of an OPEN sequential or
random fi le, or returning the status of the buffers in an OPEN
communication channel.
Syntax LOF(<nexp>)
(<nexp>) is the number assigned to the fi le or communication channel
when it was OPENed.
Remarks
LOF can also be used to check the receive or transmit buffer of the specifi ed
communication channel:
• If a channel is OPENed for INPUT, the remaining free space (bytes) in
the receive buffer is returned.
• If a channel is OPENed for OUTPUT, the remaining number of characters
to be transmitted from the transmit buffer is returned.
Examples The fi rst example illustrates how the length of the fi le "Pricelist" is
returned:
10 OPEN "PRICELIST" AS #5
20 A%=LOF(5)
30 PRINT A%
. . . .
. . . .
The second example shows how the number of free bytes in the receive buffer
of communication channel "uart2:" is calculated:
100 OPEN "uart2:" FOR INPUT AS #2
110 A%=LOF(2)
120 PRINT A%