Installed images

[lesley_4]

How can I determine if an image is installed from within a command file?

I want the connad file to take different action if a program is an installed image and different action if it is not.

ie
$ if installed_image (filename) = "Y"
$ then
$ write sys$output "Fn is installed"
$ else
$ write sys$output "Fn is not installed"
$ endif

[Phil.Howell]

see help lex f$file
something like this should do
if .not. f$file_attributes(p1,"known")
Phil

[David Jones_21]

Use f$file() with the KNOWN item. One gotcha is the file specification cannot contain a version specification and has to preserve concealed devices. For example:

$ spec = "sys$system:set.exe"
$ write sys$output f$file(spec,"KNOWN")
TRUE
$ spec2 = f$parse(spec)
$ write sys$output f$file(spec2,"KNOWN")
FALSE
$ spec = "disk$avms82r1:[vms$common.sysexe]set.exe"
$ write sys$output f$file(spec,"KNOWN")
FALSE

[lesley_4]

Thanks Phil & David

Lesley

[Hein van den Heuvel]

Lesley, welcome to the ITRC OpenVMS Forum.

Please consider recognizing the effort of the responders and the quality of the answer by assigning 'points'. Follow the 'How to earn points' link on your left, and check the FAQ for a minute in return for 'free support, worth every penny'.

http://forums1.itrc.hp.com/service/forums/helptips.do?#28

Regards,
Hein van den Heuvel

( 0 points for this reply please )

[John Gillings]

> One gotcha is the file specification cannot contain a version specification and has to preserve concealed devices.

It's even more of a gotcha than that! The file specification must translate to EXACTLY the same filespec used to install the image. This is part of "known file paranoia".

General rule: DEFINE a /SYSTEM/EXEC logical name pointing to any image to be installed which doesn't reside in a system directory. Always use it to INSTALL or reference the image, and everything will work as you expect.