Access denied

[KenDown]

Can anyone tell me why the bit of code here throws up an "Access denied" error? I get the same error if I don't delete the temporary file but then call the routine a second time (which would try to overwrite Temp.bmp)

Reading the help file indicates that to clear images out of memory one needs to call PROC_imgExit followed by PROC_imgINIT and doing so does indeed allow me to delete the file, but it also disables the library so that no further images are displayed.

Code: Select all

      INSTALL @lib$+"ImgLib"
      PROC_imgInit
      l%=0:t%=0:w%=1920:h%=1080
      OSCLI("SCREENSAVE "+@dir$+"Temp.bmp "+STR$l%+","+STR$t%+","+STR$w%+","+STR$h%)
      t%=FN_imgLoad(@dir$+"Temp.bmp")
      OSCLI("DEL "+CHR$34+@dir$+"Temp.bmp"+CHR$34)

[baz4096]

Hi Ken,

We had a web hosting outage earlier that prevented Richard from replying to this post.
Richard's message would have been as follows:

Can anyone tell me why the bit of code here throws up an "Access denied"
error?

@dir$ is the directory containing your
BASIC program, as such you should never attempt to write to
it since it may be read-only - and is likely to be if you
'compile' your program to an executable. The only pre-defined
directories to which you may safely write are
@tmp$ and @usr$.

Also, it makes no sense to put a file path in quotes in the *DEL command
but the same path not in quotes in the *SCREENSAVE command:

Code: Select all

       OSCLI("SCREENSAVE "+@dir$+"Temp.bmp
"+STR$l%+","+STR$t%+","+STR$w%+","+STR$h%)
       OSCLI("DEL "+CHR$34+@dir$+"Temp.bmp"+CHR$34)

If quotes are needed (and they generally will be) they are needed in
both.
--------------------------------------------------------------------

Richard.

[KenDown]

Thank you, Richard.

My program (which is compiled) is on my D: drive, but can equally well run off a USB stick or other portable drive, so access permissions should be fine. However when I changed @dir$ to @usr$ or @tmp$ everything worked as expected and the file deleted happily. Is this some deliberate restriction on @dir$? Is there a work-around?

You are correct about the quotes. I stuck them in out of desperation. * commands don't usually need them unless there is a space or some other "illegal" character in the filename.