more elevate docs

diff --git a/basis/elevate/elevate-docs.factor b/basis/elevate/elevate-docs.factor
index d7bcbbcfd4881ad1215ff2765b3ad81a2db65493..8e2541b547709372840754f69554d16f2f908f97 100644 (file)
--- a/basis/elevate/elevate-docs.factor
+++ b/basis/elevate/elevate-docs.factor
@@ -1,13 +1,35 @@
 USING: arrays elevate.private help.markup help.syntax
-io.launcher kernel strings system ;
-
+io.launcher kernel strings system words ;
 IN: elevate
 
+: $say-shexw ( children -- )
+    drop "ShellExecuteW" dup "windows.shell32" lookup-word [ ($link) ] [ $snippet ] if ;
+
 ABOUT: elevate
 
 ARTICLE: "elevate" "Elevated permissions API"
-    "Ported from " { $url "https://github.com/barneygale/elevate" "Barney Gale's implementation" } " in Python."
+    "The " { $vocab-link "elevate" } " vocabulary provides abstractions for running programs with elevated (administrator) privileges (permissions). It allows code to relaunch itself or other programs with administrator privileges after requiring a password."
+    $nl
+     "This vocabulary is inspired by and ported from " { $url "https://github.com/barneygale/elevate" "Barney Gale's elevate.py" } "."
     { $subsections elevate elevated lowered }
+    
+    "However, there are many caveats: " { $link "elevate.bugs" }
+;
+
+ARTICLE: "elevate.bugs" "Elevate bugs and caveats"
+    "There are many inherent platform-specific limitations and workarounds in the " { $vocab-link "elevate" } " elevated privileges API. This article explains and documents them for the curious, future maintainers, or those who run into problems."
+    { $heading "macOS" }
+    "On Apple macOS, an Applescript command is attempted for a graphical method before " { $snippet "sudo" } ". Sometimes, this command appears to execute incorrectly due to the group of the user owning the calling process. On macOS, " { $snippet "sudo" } " suffers the drawback mentioned below for applications which do not have a TTY connected."
+    { $heading "Linux, *BSD and other Unix-likes" }
+    "On Linux, " { $snippet "gksudo" } ", " { $snippet "kdesudo" } ", and " { $snippet "pkexec" } " are all attempted graphical methods before " { $snippet "sudo" } "."
+    { $list 
+        { { $snippet "pkexec" } " is the preferred and most secure graphical authentication method on Linux. It is undesirable for Factor applications, because unless a certain rare global registry value is set, " { $snippet "pkexec" } " does not set the " { $snippet "$DISPLAY" } " environment variable, and thus cannot launch graphical applications despite being a graphical program itself. It is tried after " { $snippet "gksudo" } " and " { $snippet "kdesudo" } " but before " { $snippet "sudo" } "." }
+        { { $snippet "gksudo" } " and " { $snippet "kdesudo" } " are deprecated, but still present on most GTK- and KDE-based systems, respectively. GTK is more widespread than KDE so " { $snippet "gksudo" } " is tried before " { $snippet "kdesudo" } ". These old-fashioned methods ensure that the launched application can be graphical, so they are preferred for Factor." }
+        { { $snippet "sudo" } " is the final and most robust strategy tried on Linux. It is text-based, so it requires the calling process to have an active and accessible terminal (TTY) for user authentication. If the calling Factor application was started from the desktop graphical shell rather than from a TTY, this method will fail." }
+    }
+    "On other Unix-like or POSIX-like operating systems, " { $snippet "sudo" } " is the only consistently popular method of authentication, and it suffers the same drawback on other Unix-likes as on Linux." 
+    { $heading "Windows" }
+    { "On Windows, the FFI word " { $say-shexw } " is used with the verb " { $snippet "runas" } " to force the new process to run with User Account Control." } 
 ;
 
 HELP: elevated