The FREAD function reads a component from the
file. The syntax is:
R FREAD TIENO COMPONENT {PASS}
TIENO is the tie number you used to tie or create
the file (or the tie number returned by APLX if you tied or created it using 0
instead of your own tie number). If you
tied the file using a pass number, you must provide the same pass number, as
the PASS parameter.
The parameter COMPONENT is the component number you
want to read. This must be an integer
in the range Lowest existing component number to Highest existing
component number.
The explicit result is the data (array or overlay) last
written to that component by any user.
If the component number does not exist, APLX will generate
an error COMPONENT NOT IN FILE (error code 20
in LER, or 6 3 in ET).