I need a way to check if a pdf file is open?

I've created a lisp rutine that prints a pdf of the current view.

The rutine overwrites any existing pdf, but errors out if the file is already open.

I would like to make this a little cleaner, so I'm looking for a way to check if the pdf file is already open and if so offer an option to save to a new name.

I know there is an option to do this in doslib, but i would prefer to do it with lisp only.

Does anybody know a way to check if a pdf file is open?

Here's one [crude] way:

;; filename = filename of file to test
;; Returns T if specified file is open

(defun _FileOpen-p ( filename / f )
 (if (setq f (open filename "a"))
   (close f)
   t
 )
)

Hi Mac, Thank you for the reply.

I actually did try the open command but with the write option (open filename "w")

This just Leaves a corrupted file as the function deletes any content even if the file is closed and nothing is written to it.

I just expected the same to be true about append since it starts by adding a carriage return, but maybe I was a little hasty.

Is the PDF stil working after being closed using this method?

(sorry I'm not at my workstation right now so I can't check it out)

Not crude at all, rather elegant in my opinion

I just expected the same to be true about append since it starts by adding a carriage return, but maybe I was a little hasty.

The append mode of the open function doesn't add a carriage return, the data is appended to the end of the existing data.

Is the PDF stil working after being closed using this method?

As far as I can tell, yes.

Not crude at all, rather elegant in my opinion

I'm glad you think so, I just prefer less intrusive methods

Lee's method is working nicely, and the tested PDF appears normal when opened after _FileOpen-p.

Obviously more overhead than necessary here, but when I looked into the GetFile properties & methods (from FileSystemObject), I was suprised to find there was no IsOpen method... at least without writing code in pure .NET that is. Haven't looked into WScript.Shell, but again, more overhead than is necessary.

Cheers!

> Lee Mac

I already went ahead and used the doslib function "dos_openp", but will implement this tomorrow.

Thank you for helping me out!

I saw your tutorial on remembering a dialogs position. That was exactly what I was looking for in another project of mine, so thank you for that as well :wink:

I saw your tutorial on remembering a dialogs position. That was exactly what I was looking for another project of mine, so thank you for that as well :wink:

Good stuff! You're welcome

Lee's method is working nicely, and the tested PDF appears normal when opened after _FileOpen-p.

 

Obviously more overhead than necessary here, but when I looked into the GetFile properties & methods (from FileSystemObject), I was suprised to find there was no IsOpen method... at least without writing code in pure .NET that is. Haven't looked into WScript.Shell, but again, more overhead than is necessary.

 

Cheers!

As I already tried out the open function and failed, I was expecting something along these lines, so thank you for contributing.

Cheers and beers to you to.

As I already tried out the open function and failed, I was expecting something along these lines, so thanks for you for contributing.

 

Cheers and beers to you to.

See, now I feel like I have to post an example! LoL

Like I said earlier, WAY more overhead than necessary (given Lee's succinct example), for the same result:

(defun _FileOpen-p (filePath / *error* fso file err flag)
 (vl-load-com)

 (defun *error*  (msg)
   (if (or file fso)
     (foreach x  (list err file fso)
       (vl-catch-all-apply 'vlax-release-object (list x))))
   (cond ((not msg))                                                   ; Normal exit
         ((member msg '("Function cancelled" "quit / exit abort")))    ; <esc> or (quit)
         ((princ (strcat "\n** Error: " msg " ** "))))                 ; Fatal error, display it
   (princ))
 
 (if (and (setq fso (vlax-get-or-create-object "Scripting.FileSystemObject"))
          (setq file (vlax-invoke fso 'getfile filePath)))
   (progn
     (if (vl-catch-all-error-p
           (setq err
                  (vl-catch-all-apply
                    'vlax-invoke
                    (list file 'openastextstream 8 -2))))
       (setq flag T)
       (setq flag nil))
     (foreach x  (list err file fso)
       (vl-catch-all-apply 'vlax-release-object (list x)))
     flag)
   (cond (fso (prompt "\n** Unable to invoke the \"GetFile\" method ** "))
         ((prompt "\n** Unable to create \"Scripting.FileSystemObject\" object ** ")))))

OpenAsTextStream linky

... And thank you kindly, for the beer!

Like I said earlier, WAY more overhead than necessary...

lol I think you just wanted to use the openastextstream method

Anyway, here is another way:

(defun _FileOpen-p ( filename )
 (not (vl-file-rename filename filename))
)

lol I think you just wanted to use the openastextstream method

 

Anyway, here is another way:

 

(defun _FileOpen-p ( filename )
 (not (vl-file-rename filename filename))
)

Even sweeter, this works perfectly and within a single set of parenthesis no less.

lol I think you just wanted to use the openastextstream method

:lol:

Anyway, here is another way:

 

(defun _FileOpen-p ( filename )
 (not (vl-file-rename filename filename))
)

Even sweeter, this works perfectly and within a single set of parenthesis no less.

Well said, hemuni. :wink:

I'm embarrassed to admit that I first considered renaming (after your initial suggestion, that is), but I wasn't *sure*, and never tried it before writing the Scripting.FileSystemObject code.

Renaming the file as itself is brilliantly simple...

Cheers!

Cheers guys

Neither one of these routines work for me.  If if run it with the specified file open, I get nil. If I run it with it closed, I get nil. What am I doing wrong? 

Ok, I discovered that it works for a PDF file but not for a TXT file.

Thanks