If varname contains namespace qualifiers, the local variable's name is the unqualified name of the global variable, as determined by the namespace tail command.
varname is always treated as the name of a variable, not an array element. An error is returned if the name looks like an array element, such as a(b).
proc reset {} {
global a::x
set x 0
}
This procedure accumulates the strings passed to it in a global buffer, separated by newlines. It is useful for situations when you want to build a message piece-by-piece (as if with puts) but send that full message in a single piece (e.g. over a connection opened with socket or as part of a counted HTTP response).
proc accum {string} {
global accumulator
append accumulator $string \n
}