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ExamineDirectory() :: Add Command To Get Number of Entries
Posted: Fri Jun 30, 2017 2:17 pm
by Tristano
Currently there is no way to know how many entries
ExamineDirectory() found. The only way around it seems to be restorting to a
While NextDirectoryEntry() loop with a custom counter — something like this:
Code: Select all
Directory$ = GetHomeDirectory()
If ExamineDirectory(0, Directory$, "*.*")
count = 0
While NextDirectoryEntry(0)
count + 1
Wend
Debug("Total items found: " + Str(count))
EndIf
It would very handy to have a command that returns the actual number of entries found by
ExamineDirectory() — just like
ListSize() does for lists! — so we could now the exact number of matched entries beforehand, without resorting to any loops.
Maybe it could be called
DirectoryEntriesSize() (or something along those lines).
Such a command would allow to execute a boolean test on the examined Directory before actually iterating through a
While NextDirectoryEntry() loop! — For example:
Code: Select all
Directory$ = GetHomeDirectory()
If ExamineDirectory(0, Directory$, "*.txt")
If DirectoryEntriesSize(0)
; At least one *.txt file was found ...
While NextDirectoryEntry(0)
; Do something with the txt files ...
Wend
Else
Debug("No txt files found!")
EndIf
EndIf
And, of course, it would allow to fork code execution based on the number of entries:
... and quickly compare results from two different directories:
Code: Select all
If DirectoryEntriesSize(0) > DirectoryEntriesSize(1)
This command would allow good code optimization when dealing with directories — both in execution speed as well as having to write less code.
Re: ExamineDirectory() :: Add Command To Get Number of Entri
Posted: Fri Jun 30, 2017 5:17 pm
by freak
There is no way to know the number of entries without iterating all of them. If we added such a command it would be exactly like the code you posted.
Re: ExamineDirectory() :: Add Command To Get Number of Entri
Posted: Sat Jul 01, 2017 11:03 am
by Tristano
I see. It's a pity, it would have been useful.
Even though it wouldn't optimize execution time, wouldn't it still be worth it because it allows to get this info with a single command instead of writing a whole block?
At least it would make cleaner code.
Re: ExamineDirectory() :: Add Command To Get Number of Entri
Posted: Sat Jul 01, 2017 11:06 am
by Little John
Tristano wrote:Even though it wouldn't optimize execution time, wouldn't it still be worth it because it allows to get this info with a single command instead of writing a whole block?
At the beginning of your first post here, you almost wrote such a function yourself with a few lines ...
Re: ExamineDirectory() :: Add Command To Get Number of Entri
Posted: Sat Jul 01, 2017 3:12 pm
by Tristano
Little John wrote:Tristano wrote:Even though it wouldn't optimize execution time, wouldn't it still be worth it because it allows to get this info with a single command instead of writing a whole block?
At the beginning of your first post here, you almost wrote such a function yourself with a few lines ...
... true! Surely, writing some custom procedures to similar tasks is not a big issue. But lazyness is a blessing!
I didn't realize that it wasn't possible to know the items total number before actually iterating them — I now guess that this is because ExamineDirectory() relies on OS functionality.
Even a simple boolean True/False value would have been a good feature, just to check if there are any entries at all.
What can I say ... I tried
— after all features requests are about ideas of what might be useful, provided they are implementable.
Re: ExamineDirectory() :: Add Command To Get Number of Entri
Posted: Sat Jul 01, 2017 3:33 pm
by Little John
Tristano wrote:Even a simple boolean True/False value would have been a good feature, just to check if there are any entries at all.
I did understand your original wish.
However, in the meantime freak has explained the situation.
Re: ExamineDirectory() :: Add Command To Get Number of Entri
Posted: Sat Jul 01, 2017 8:58 pm
by helpy
Tristano wrote:Even a simple boolean True/False value would have been a good feature, just to check if there are any entries at all.
NextDirectory() already does a similar thing! If there is no entry at all it returns zero!
Re: ExamineDirectory() :: Add Command To Get Number of Entri
Posted: Sun Jul 02, 2017 4:21 am
by tj1010
this would be nice, but it'd still have to do this because extension mask:
Code: Select all
Procedure.l countem(path$,mask$)
Protected dir.l
Protected counter.l
CompilerIf #PB_Compiler_OS=#PB_OS_Windows
If Mid(path$,Len(path$),1)<>"\" : path$=path$+"\" : EndIf
CompilerElse
If Mid(path$,Len(path$),1)<>"/" : path$=path$+"/" : EndIf
CompilerEndIf
If FileSize(path$)=-2
dir=ExamineDirectory(#PB_Any,path$,mask$)
If dir
While NextDirectoryEntry(dir)
If DirectoryEntryName(dir)<>".." And DirectoryEntryName(dir)<>"."
If DirectoryEntryType(dir)=#PB_DirectoryEntry_File
counter=counter+1
Else
CompilerIf #PB_Compiler_OS=#PB_OS_Windows
counter=counter+countem(path$+DirectoryEntryName(dir)+"\",mask$)
CompilerElse
counter=counter+countem(path$+DirectoryEntryName(dir)+"/",mask$)
CompilerEndIf
EndIf
EndIf
Wend
FinishDirectory(dir)
EndIf
EndIf
ProcedureReturn counter
EndProcedure
Debug countem(PathRequester("Pick A Folder",GetCurrentDirectory()),"*.*")
Re: ExamineDirectory() :: Add Command To Get Number of Entri
Posted: Sun Jul 02, 2017 6:05 am
by Dude
nvm
Re: ExamineDirectory() :: Add Command To Get Number of Entri
Posted: Sun Jul 02, 2017 6:55 am
by Little John
It seems you mean
NextDirectoryEntry().
helpy wrote:If there is no entry at all it returns zero!
It returns 0 on first call only in case of an error. There is always the entry "." and except for thr root directory there is also ".." (at least on Windows).
Re: ExamineDirectory() :: Add Command To Get Number of Entri
Posted: Sun Jul 02, 2017 7:51 am
by helpy
Little John wrote:
It seems you mean
NextDirectoryEntry().
Yes! You are right!
Little John wrote:helpy wrote:If there is no entry at all it returns zero!
It returns 0 on first call only in case of an error. There is always the entry "." and except for thr root directory there is also ".." (at least on Windows).
Not always. I only tested mask *.pdf and *.txt
In this case no entry "." or ".." is returned....
Yes. You are right, we should always do tests, if entry is a file or a directory and if entry is "." or "..".
Re: ExamineDirectory() :: Add Command To Get Number of Entri
Posted: Sun Jul 02, 2017 8:00 am
by Little John
helpy wrote:Not always. I only tested mask *.pdf and *.txt
In this case no entry "." or ".." is returned....
Doh, I didn't think of the mask ... You are right.
Re: ExamineDirectory() :: Add Command To Get Number of Entri
Posted: Mon Jul 03, 2017 2:51 am
by Olliv
First remark
Problem in your wish is that an entry can be more than just one thing :
1) a file
2) either a sub-directory
If you explore a directory one first time to get the number of entries, the new idea you will have is a new feature to get the count of files in one directory.
Also PureBasic concept is not actually based to a stored structured syntax, usable like this :
Code: Select all
Structure DirContent
TotalCount.I
FileCount.I
EndStructure
Define DirCtn.DirContent
GetDirContent(DirCtn)
Debug Str(DirCtn\FileCount) + " files"
Debug Str(DirCtn\TotalCount) + " entries"
If it was, it should :
Code: Select all
ExamineDirectoryContent()
Debug Str(GetFileCount() ) + " files"
Debug Str(GetDirTotalCount() ) + " entries"
Then it would not be
one but
three new statements !
2nd remarkIt seems that '/' is cross-platform. No need to use a compiler directive to pre-select a '/' character or a '\' character, depending of the OS. Do I mistake?
3nd remarkI am surprised it is unable to get more infos about a directory. Is this due to various length of file name?
Re: ExamineDirectory() :: Add Command To Get Number of Entri
Posted: Mon Jul 03, 2017 9:13 am
by Tristano
Olliv wrote:2nd remarkIt seems that '/' is cross-platform. No need to use a compiler directive to pre-select a '/' character or a '\' character, depending of the OS. Do I mistake?
Windows will accept "/" as a path separator, but any commands dealing with file paths will always return "\" as a separator because it's Win default. So, any cross-platform code will have to take in account that on Win when retriving file/folder paths.
From this thread it seems like there can't be a single solution to fit all needs. Probably the best solution would be to have a collection of different PB examples/procedures to pick from to handle this (ie: cross-platform, platform-dependent, etc.).
About the "." and ".." entries found on Windows, are there similar equivalents on Linux and Mac? In my code I already handle "." and ".." on Win OS, but I was wondering if and what to except on Mac (which I don't have access to) in order to make it cross platform.
PS: I think that the documentation ought to mention "." and ".." on Win, and other similar cases on other OSs, so users can keep it in mind for cross-platform code's sake.
Re: ExamineDirectory() :: Add Command To Get Number of Entri
Posted: Mon Jul 03, 2017 12:04 pm
by tj1010
Symlinks and alt-streams are the only real issues. My code works on Debian, OSX, and Windows with no problems. I could of used RunProgram for privilege escalation.
I avoid API as much as possible especially on Linux..