fork -- fork the current Tcl process




Forks the current Tcl process. fork returns zero to the child process and the process number of the child to the parent process. If the fork fails, a Tcl error is generated.

If an execl is not going to be performed before the child process does output, or if a close and dup sequence is going to be performed on stdout or stderr, then a flush should be issued against stdout, stderr and any other open output file before doing the fork. Otherwise characters from the parent process pending in the buffers will be output by both the parent and child processes.