The FPARSE intrinsic parses and validates a file designator
string to determine if it is syntactically correct. You can employ
this intrinsic to check a formal file designator representing a
file before attempting to open the file with HPFOPEN/FOPEN.
MPE/iX file designators used for the file system and two user interface
commands include a remote environment ID (envid). This
allows the user to indicate that a file is
to be accessed from a remote environment established by the user
with the DSLINE or REMOTE HELLO command. FPARSE
facilitates the changes required for the file
designator extension. It provides the only location within MPE/iX
where file designators are parsed and syntax is checked.
The following are examples of the items and the
vectors array pair. The order of entries in the
vectors array corresponds to the order of items in the
items array. Each 32-bit entry in the vectors
array returns the byte offset of the item in the first half-word, and the
length in bytes of the item in the second half-word. However, the last entry of
the vectors array has a different meaning from that of the
other entries: the second half-word gives the total length of the file
string, and the first half-word gives a system file code when applicable.
In Figure 3-3 "Illustration of FPARSE Usage"
the file string is
"FILENAME/LOCKWORD.GROUP.ACCOUNT:ANIMAL.INDDCL.HPBCG":Figure 3-3 Illustration of FPARSE Usage
The items array, as illustrated above, can be listed in any
order or can be left unspecified if not required.
In Figure 3-4 "Illustration of FPARSE Usage",
below, the file string is "*FILENAME:ANIMAL":Figure 3-4 Illustration of FPARSE Usage
In Figure 3-5 "Illustration of FPARSE Usage",
below, the file string is "$OLDPASS":Figure 3-5 Illustration of FPARSE Usage
Note that "$" is a special exception to the rules of file
names and is considered part of the file name, unlike "*", which is not.
Using Command Interpreter Variables and Expressions Within File Designators