mcwill@prlhp1.prl.philips.co.uk (Iain McWilliams) (04/11/88)
I wish to use F$PARSE to create a full file spec in a command file, when I only supply part of the filename as a parameter. The problem arises when the default spec is to contain a logical symbol set up as a search list ==> ---------------------------------------- $assign [unit],[subsystem],[project] search$path: !usually in login.com $full_spec = F$PARSE(p1,"search$path:standard.dat") $if f$search(full_spec) .nes. "" then write sys$output p1," found" ---------------------------------------- Under these circumstances, F$PARSE will translate the logical into the first element in the search list, so that if the file exists elsewhere in the search list, F$SEARCH cannot find it. There is a field "parse-type" which I thought may offer a solution, but it will stop iterative translation only when it encounters a logical name with the 'concealed' attribute, and that attribute is only valid for an equivalence string which is a physical device. Does anyone have a solution, or has the lexical been changed in any recent (post 4.5) release Any suggestions received with thanks, -- Iain.
rrk@byuvax.bitnet (04/15/88)
To the best of my knowlege, this can't be done. If you are calling sys$parse
and sys$search, they store special information in the FAB which deals with
search path logicals. When you call the f$parse lexical, it throws this
information away and all f$search has to go on is the first translation.
You have to make the parse and search use the same FAB block, and I think
this cannot be done from DCL. On the other hand, if you can get away without
calling f$parse and only call f$search, f$search calls sys$parse first anyway
and uses the same FAB for its sys$search calls. Unfortunately, this makes
it impossible to provide filename defaults as f$parse allows you to do.
AMMON::RAYrrk@byuvax.bitnet (04/16/88)
It just occurred to me ... there is a way to make it work, but it is very
clumsy. That is...you make your logical search path be a concealed device
definition:
$ DEFINE/TRANS=CONCEALED SEARCH$PATH DEV1:[DIR1.],DEV2:[DIR2.],DEV3:[DIR3.]
Then, construct your filename to be searched as:
search$path:[000000]filename.ext
Since it is concealed device translation, f$parse doesn't translate the
logical name, leaving it for f$search to properly expand into the search
list.
AMMON::RAYBJH@V3.INFERENCE.COM (Brian Hagerty x 111) (04/21/88)
Answering Iain McWilliams query ... > I wish to use F$PARSE to create a full file spec in a command file, when I > only supply part of the filename as a parameter. The problem arises when the > default spec is to contain a logical symbol set up as a search list [...] The following code seems to meet your needs: $ define search$path [unit],[subsystem],[project] $ $ inquire file "File" $ $ file = f$parse(file,"standard.dat") $ name = f$parse(file,,,"name") $ type = f$parse(file,,,"type") $ if f$search(file).eqs."" then file = f$search("search$path:''name'''type'") $ $ if file.nes."" then write sys$output file," found!" $ exit $ deck Brian Hagerty [sic] BJH @ V3.INFERENCE.COM Network Manager Inference Corporation Lost Angeles, CA $ eod! -------