... The XPA messaging system provides seamless communication between many kinds of Unix programs, including X programs and Tcl/Tk programs. It also provides an easy way for users to communicate with XPA-enabled programs by executing XPA client commands in the shell or by utilizing such commands in scripts. ... A program becomes an XPA-enabled server by defining named points of public access through which data and commands can be exchanged with other client programs (and users). ... XPA User Programs . ...

... will give a .\" real vertical bar. ... It also provides an easy way for users to communicate with these XPA-enabled programs by executing \s-1XPA\s0 client commands in the shell or by utilizing such commands in scripts. ... PP A program becomes an XPA-enabled server by defining named points of public access through which data and commands can be exchanged with other client programs (and users). ... Client access also is supported at the command line via a suite of high-level programs. ...