User exit u01ad retrieves a value from an attribute of an item in a file. The next line of the Proc specifies the file information.
u01ad file.name item-ID attribute.ref code.number
file.name | Name of the file. If the file name is prefixed with an asterisk, the dictionary portion of the file is accessed. | |
item-ID | Item name. | |
attribute.ref | Attribute name (or number). | |
code.number | a | Outputs to the alternative output buffer. |
p | Outputs to the primary input buffer. | |
s | Outputs to the current output buffer. | |
t | Outputs to the terminal. | |
v | Verifies that the file exists. | |
va | Verifies that the attribute exists. |
This function allows indirect references to values from the input and output buffers by using these special symbols:
% | Indicates the current input buffer value. |
# | Indicates the current output buffer value. |
a0(tfile.reference;xn;; a/amc)where file.reference is the name of the file, n is the n value to retrieve, and a/amc is the attribute-mark count to use.
Direct Reference | |
pq u01ad control-file co.name 1 s xcan’t find co.name or control.file |
Reads attribute 1 of the item called co.name in the file named control-file and places it in the current output buffer. |
Indirect Reference | |
pq u01ad %2 %3 %4 p xsomething went wrong... d0 |
Reads the attribute number as defined in the fourth location of the input buffer, using the item-ID from the third location and the file name from the second location. |