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Dmitry Maslennikov · Jun 27, 2018

In addition to other answers, if want to operate with bits, you can use functions:

  • $zhex - converts integer to hex and vice versa, be careful with type of variables. If you pass string it will convert from hex to dec, if you will pass integer it will convert from dec to hex.
  • $factor - converts integer to a $bit string
  • $bit (with bunch of $bit* functions) - operates with bitstrings.
  • You may possible need some encryption functions, you can find
  • And possible zlib, $system.Util.Compress and $system.Util.Decompress from class %SYSTEM.Util 

If you are going to work with H.264, I would not recommend to try to implement it in COS, it will not be fast enough. I'm not very know with this technology but I'm sure I know, it is too complicated and encoding should work in GPU. But it is impossible with Caché. I don't know why exactly do you need it, but I would recommend you to look at external tool ffmpeg, which is very useful and leader on work with video. And I think you can connect ffmpeg.dll, to work from Caché with $zf functions.

Dmitry Maslennikov · Jun 21, 2018

Well, there is mostly only one reason, why you can't mount your database and this issue mostly happens when anybody tries to migrate between different versions on different machines. And it is different localization settings. Like, your database uses some national global collation, and you try to copy it to the instance with different settings, where this collation does not supported. You should find mention about  wrong collation in cconsole.log. So, then, you should set the same NLS, as in the first system and try to mount again.

Another possible reason is different blocksize in the Database. By default Caché uses 8KB blocks, but it is possible to have different block size, and instance should be configured for this particular blocksize, as well. cconsole.log should also contain error in this case.

Some other issues, which you can face, but they do not prevent database to be mounted.

  • 8-bit or Unicode, when you install Caché you still able to choose it, when Ensemble, HealthShare, and IRIS is Unicode only. In this case, if your data not in English, possible data should be converted from 8-bit codepage to Unicde.
  • cache.lck file next to CACHE.DAT, it is a lock file, prevents to mount database with exclusive access. But Database in this case should be mounted in read-only mode.
Dmitry Maslennikov · Jun 21, 2018

Function $zf(-1) just executes a command passed as the second argument, you passed only file name. it is not complete, you should add command del  for Windows.

set status = $zf(-1, "del c:\sys\text.txt")

it should return 0 if the command was successful.

If you want just delete a file, you can use %File class, useful for many different operations with files and folders.

set result = ##class(%File).Delete("c:\sys\text.txt")
Dmitry Maslennikov · May 1, 2018

We are not WRC, it is developer community.

As Tom already mentioned, in Caché class is not just as routine, it is like a bunch of objects defined in %Dictionary package, methods code can be found with %Dictionary.MethodDefinition or %Dictionary.CompiledMethodDefinition, depends on the situation.

But it is possible to get a text of class like you can in Studio

%Compiler.UDL.TextServices with methods GetTextAsStream, GetTextAsFile and etc., and convert back from text to class

In versions since 2016.2 you can use export to file in UDL format with $system.OBJ.ExportUDL()

Dmitry Maslennikov · Apr 16, 2018

I would recommend to use more suitable class for it. %Stream.FileCharacter when you can set TranslateTable property

Set stream=##class(%Stream.FileCharacter).%New()
Set sc=stream.LinkToFile("c:\myfile.txt")
Set stream.TranslateTable = "UTF8"
While 'stream.AtEnd {
	Set line=stream.Read()
	; Process the chunk here
}

And you don't need any conversions after that