unknown -- handle attempts to use non-existent commands
arg arg ...
This command is not a core part of Tcl, but Tcl will invoke it if it does exist (that is, if a function called
has been written and linked to Tcl in the current application). If the Tcl interpreter encounters a command name for which there is not a defined command, then Tcl checks for the existence of a command named
. If there is no such command, then the interpreter returns an error. If the
command exists, then it is invoked with arguments consisting of the fully-substituted name and arguments for the original non-existent command. The
command typically does things like searching through library directories for a command procedure with the name
, or expanding abbreviated command names to full-length, or automatically executing unknown commands as sub-processes. In some cases (such as expanding abbreviations)
will change the original command slightly and then (re-)execute it. The result of the
command is used as the result for the original non-existent command.
© 2003 Caldera International, Inc. All rights reserved.
SCO OpenServer Release 5.0.7 -- 11 February 2003