Tornado

5
Shell
5.4.2 Automatic Name Demangling
Many shell debugging and system information functions display addresses
symbolically (for example, the l( ) routine). This might be confusing for C++,
because compilers encode a function’s class membership (if any) and the type and
number of the function’s arguments in the function’s linkage name. The encoding
is meant to be efficient for development tools, but not necessarily convenient for
human comprehension. This technique is commonly known as name mangling and
can be a source of frustration when the mangled names are exposed to the
developer.
To avoid this confusion, the debugging and system information routines in
WindSh print C++ function names in a demangled representation. Whenever the
shell prints an address symbolically, it checks whether the name has been
mangled. If it has, the name is demangled (complete with the function’s class
name, if any, and the type of each of the function’s arguments) and printed.
The following example shows the demangled output when lkup( ) displays the
addresses of the xmin( ) functions mentioned in 5.4.1 Overloaded Function Names,
p.191.
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-> lkup "xmin"
_xmin(double,double) 0x003fe710 text (templex.out)
_xmin(long,long) 0x003fe754 text (templex.out)
_xmin(int,int) 0x003fe73a text (templex.out)
_xmin(float,float) 0x003fe6ee text (templex.out)
value = 0 = 0x0
5.5 Shell Line Editing
The WindSh front end provides a history mechanism similar to the UNIX
Korn-shell history facility, including a built-in vi-like line editor that allows you to
scroll, search, and edit previously typed commands. Line editing is available
regardless of which interpreter you are using (C or Tcl 6 ), and the command history
spans both interpreters—you can switch from one to the other and back, and scroll
through the history of both modes.
You can control what characters to use for certain editing commands. The input
keystrokes shown in Table 5-14 (5.3.13 Terminal Control Characters, p.186) are set by
6. The WindSh Tcl-interpreter interface is described in 5.7 Tcl: Shell Interpretation, p.198.
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