# The allowed child variables already have been set by Tcl_MakeSafe(3)

    # Source init.tcl and tm.tcl into the child, to get auto_load and
    # other procedures defined:

    if {[catch {::interp eval $child {
	source [file join $tcl_library init.tcl]
	source -encoding utf-8 [file join $tcl_library init.tcl]
    }} msg opt]} {
	Log $child "can't source init.tcl ($msg)"
	return -options $opt "can't source init.tcl into slave $child ($msg)"
    }

    if {[catch {::interp eval $child {
	source [file join $tcl_library tm.tcl]
	source -encoding utf-8 [file join $tcl_library tm.tcl]
    }} msg opt]} {
	Log $child "can't source tm.tcl ($msg)"
	return -options $opt "can't source tm.tcl into slave $child ($msg)"
    }

    # Sync the paths used to search for Tcl modules. This can be done only
    # now, after tm.tcl was loaded.