exists -proc -> exists -command

`exists -command` subsumes `exists -proc`

This test is generally checking whether the command exists, rather than some proc that is overriding it.

Currently `class` is a proc but this may not always be so.

webif/lib/browse.class

@@ -1,7 +1,7 @@
 
 require system.class plugin
 
-if {![exists -proc class]} { package require oo }
+if {![exists -command class]} { package require oo }
 class dir {}
 class browse {}
 

webif/lib/clipboard.class

@@ -1,5 +1,5 @@
 
-if {![exists -proc class]} { package require oo }
+if {![exists -command class]} { package require oo }
 
 class clipboard {
 	path	"/tmp/webif.cb"

webif/lib/epg.class

@@ -1,7 +1,7 @@
 source /mod/webif/lib/setup
 
-if {![exists -proc class]} { package require oo }
-if {![exists -proc sqlite3.open]} { package require sqlite3 }
+if {![exists -command class]} { package require oo }
+if {![exists -command sqlite3.open]} { package require sqlite3 }
 
 require settings.class progressbar rsv.class mwildcard svc.class
 

webif/lib/pkg.class

@@ -1,5 +1,5 @@
 
-if {![exists -proc class]} { package require oo }
+if {![exists -command class]} { package require oo }
 
 class pkg {
 	name		""

webif/lib/queue.class

@@ -1,6 +1,6 @@
 
-if {![exists -proc class]} { package require oo }
-if {![exists -proc sqlite3.open]} { package require sqlite3 }
+if {![exists -command class]} { package require oo }
+if {![exists -command sqlite3.open]} { package require sqlite3 }
 
 class queue {
 	id		-1

webif/lib/rsv.class

@@ -1,8 +1,8 @@
 source /mod/webif/lib/setup
 
-if {![exists -proc class]} { package require oo }
-if {![exists -proc sqlite3.open]} { package require sqlite3 }
-if {![exists -proc binary]} { package require binary }
+if {![exists -command class]} { package require oo }
+if {![exists -command sqlite3.open]} { package require sqlite3 }
+if {![exists -command binary]} { package require binary }
 require settings.class system.class plugin svc.class
 
 set binaryfields aulEventToRecordInfo

webif/lib/settings.class

@@ -1,6 +1,6 @@
 
-if {![exists -proc class]} { package require oo }
-if {![exists -proc sqlite3.open]} { package require sqlite3 }
+if {![exists -command class]} { package require oo }
+if {![exists -command sqlite3.open]} { package require sqlite3 }
 
 if {![file exists /mod/etc/webif.db]} {
 	set ::settingsdb [sqlite3.open /mod/etc/webif.db]

webif/lib/svc.class

@@ -1,7 +1,7 @@
 source /mod/webif/lib/setup
 
-if {![exists -proc class]} { package require oo }
-if {![exists -proc sqlite3.open]} { package require sqlite3 }
+if {![exists -command class]} { package require oo }
+if {![exists -command sqlite3.open]} { package require sqlite3 }
 require system.class
 
 class svc {

webif/lib/system.class

@@ -3,9 +3,9 @@ source /mod/webif/lib/setup
 
 package require xconv
 
-if {![exists -proc class]} { package require oo }
-if {![exists -proc sqlite3.open]} { package require sqlite3 }
-if {![exists -proc binary]} { package require binary }
+if {![exists -command class]} { package require oo }
+if {![exists -command sqlite3.open]} { package require sqlite3 }
+if {![exists -command binary]} { package require binary }
 
 class system {}
 

webif/lib/ts.class

@@ -1,7 +1,7 @@
 
-if {![exists -proc class]} { package require oo }
-if {![exists -proc pack]} { package require pack }
-if {![exists -proc xconv]} { package require xconv }
+if {![exists -command class]} { package require oo }
+if {![exists -command pack]} { package require pack }
+if {![exists -command xconv]} { package require xconv }
 source /mod/webif/lib/setup
 require system.class tvdb.class classdump
 

webif/lib/tvdb.class

@@ -1,8 +1,8 @@
 source /mod/webif/lib/setup
 
 package require cgi
-if {![exists -proc class]} { package require oo }
-if {![exists -proc sqlite3.open]} { package require sqlite3 }
+if {![exists -command class]} { package require oo }
+if {![exists -command sqlite3.open]} { package require sqlite3 }
 require system.class xml.class
 
 set ::tvdb::apikey 1764335F804A5A91

webif/lib/xml.class

@@ -2,7 +2,7 @@
 # From https://wiki.tcl-lang.org/page/Parsing+XML
 # Keith Vetter 2004-03-01
 
-if {![exists -proc class]} { package require oo }
+if {![exists -command class]} { package require oo }
 
 class xml {
 	xml	""