Get `gn gen` to succeed on Windows

third_party/sqlite/src/tool/mkopts.tcl

+#!/usr/bin/tclsh
+#
+# This script is used to generate the array of strings and the enum
+# that appear at the beginning of the C code implementation of a
+# a TCL command and that define the available subcommands for that
+# TCL command.
+
+set prefix {}
+while {![eof stdin]} {
+  set line [gets stdin]
+  if {$line==""} continue
+  regsub -all "\[ \t\n,\]+" [string trim $line] { } line
+  foreach token [split $line { }] {
+    if {![regexp {(([a-zA-Z]+)_)?([_a-zA-Z]+)} $token all px p2 name]} continue
+    lappend namelist [string tolower $name]
+    if {$px!=""} {set prefix $p2}
+  }
+}
+
+puts "  static const char *${prefix}_strs\[\] = \173"
+set col 0
+proc put_item x {
+  global col
+  if {$col==0} {puts -nonewline "   "}
+  if {$col<2} {
+    puts -nonewline [format " %-21s" $x]
+    incr col
+  } else {
+    puts $x
+    set col 0
+  }
+}
+proc finalize {} {
+  global col
+  if {$col>0} {puts {}}
+  set col 0
+}
+
+foreach name [lsort $namelist] {
+  put_item \"$name\",
+}
+put_item 0
+finalize
+puts "  \175;"
+puts "  enum ${prefix}_enum \173"
+foreach name [lsort $namelist] {
+  regsub -all {@} $name {} name
+  put_item ${prefix}_[string toupper $name],
+}
+finalize
+puts "  \175;"