kostix 21-Jan-2007: Windows has the infamous history of playing with "standard locations" for various system and user data.
Probably the most interesting directory for a Windows developer is what called "application data" -- the directory holding per-user configuration and data directories for various programs. A well-behaving Windows program should obey this schema.
Tcl's deduction of what "~" means on Windows is sane but insufficient since it relies on some environment variables which do not present on all systems (or have insane values). More specificly, in almost all cases it's impossible to reliably guess the "application data" directory pathname using only the value of "~".
There are three ways to know where the "application data" directory is located, but not all of them are applicable on each Windows flavor:
Here's a simple reference card of what various Windows flavors offer for guessing the "application data" directory:
Win9x/ME
WinNT 4.0
Windows 2000/XP
Windows Vista
As can be seen, a well-behaving Windows program that wants to keep their configuration and local data in the standard manner has to deal with this mess and there are just two reliable ways to do this to date:
The first is much simpler and requires nothing but the core registry module. But, alas, that registry key may disappear in any future release of Windows. Which is much less likely for the SHGetSpecialFolderPath API function.
So there's a working example providing a Tcl wrapper around SHGetSpecialFolderPath using Ffidl:
package require Ffidl
ffidl::callout dll_SHGetSpecialFolderPath \
{int pointer-utf16 int int} int \
[ffidl::symbol shell32.dll SHGetSpecialFolderPathW]
proc SHGetSpecialFolderPath {what create} {
array set CSIDL {
CSIDL_DESKTOP 0
CSIDL_INTERNET 1
CSIDL_PROGRAMS 2
CSIDL_CONTROLS 3
CSIDL_PRINTERS 4
CSIDL_PERSONAL 5
CSIDL_FAVORITES 6
CSIDL_STARTUP 7
CSIDL_RECENT 8
CSIDL_SENDTO 9
CSIDL_BITBUCKET 10
CSIDL_STARTMENU 11
CSIDL_DESKTOPDIRECTORY 16
CSIDL_DRIVES 17
CSIDL_NETWORK 18
CSIDL_NETHOOD 19
CSIDL_FONTS 20
CSIDL_TEMPLATES 21
CSIDL_COMMON_STARTMENU 22
CSIDL_COMMON_PROGRAMS 23
CSIDL_COMMON_STARTUP 24
CSIDL_COMMON_DESKTOPDIRECTORY 25
CSIDL_APPDATA 26
CSIDL_PRINTHOOD 27
CSIDL_LOCAL_APPDATA 28
CSIDL_ALTSTARTUP 29
CSIDL_COMMON_ALTSTARTUP 30
CSIDL_COMMON_FAVORITES 31
CSIDL_INTERNET_CACHE 32
CSIDL_COOKIES 33
СSIDL_HISTORY 34
CSIDL_COMMON_APPDATA 35
CSIDL_WINDOWS 36
CSIDL_SYSTEM 37
CSIDL_PROGRAM_FILES 38
СSIDL_MYPICTURES 39
CSIDL_PROFILE 40
СSIDL_SYSTEMX86 41
CSIDL_PROGRAM_FILESX86 42
CSIDL_PROGRAM_FILES_COMMON 43
СSIDL_PROGRAM_FILES_COMMONX86 44
CSIDL_COMMON_TEMPLATES 45
CSIDL_COMMON_DOCUMENTS 46
CSIDL_COMMON_ADMINTOOLS 47
CSIDL_ADMINTOOLS 48
CSIDL_CONNECTIONS 49
CSIDL_COMMON_MUSIC 53
CSIDL_COMMON_PICTURES 54
CSIDL_COMMON_VIDEO 55
CSIDL_RESOURCES 56
CSIDL_RESOURCES_LOCALIZED 57
CSIDL_COMMON_OEM_LINKS 58
CSIDL_CDBURN_AREA 59
CSIDL_COMPUTERSNEARME 61
CSIDL_FLAG_DONT_VERIFY 0x4000
CSIDL_FLAG_CREATE 0x8000
CSIDL_FLAG_MASK 0xFF00
}
set bCreat [expr {$create ? 1 : 0}]
set path [string repeat \u0000 300] ;# MAX_PATH is actually 260
set ok [dll_SHGetSpecialFolderPath 0 $path $CSIDL($what) $bCreat]
if {$ok} {
set ix [string first \u0000 $path]
if {$ix > 0} {
return [string range $path 0 [expr {$ix - 1}]]
}
} else {
return {}
}
}
puts "appdata: [SHGetSpecialFolderPath CSIDL_APPDATA false]"I'm not sure, but Tk apps may probably want not to ignore the first argument of SHGetSpecialFolderPath (which is the handle of a window to assotiate any error dialog with (as I understand this)) and provide another argument (or an option) to the wrapper proc for specifying the Tk window. Then the handle of that window may be acquired using "winfo id".