Debuggers

The best way to watch what a program attempts to do is to use a debugger.

$ gdb /bin/ls
(gdb) help
List of classes of commands:
aliases -- Aliases of other commands
breakpoints -- Making program stop at certain points
data -- Examining data
files -- Specifying and examining files
internals -- Maintenance commands
obscure -- Obscure features
running -- Running the program
stack -- Examining the stack
status -- Status inquiries
support -- Support facilities
tracepoints -- Tracing of program execution without stopping the program
tui -- Text User Interface commands
user-defined -- User-defined commands