Unix in a Nutshell, 4th Edition

Examining Data

call	Call a function in the program.
delete display	Cancel one or more expressions that have been set to display when the program stops.
delete mem	Delete a memory region.
disable display	Disable one or more expressions that have been set to display when the program stops.
disable mem	Disable a memory region.
disassemble	Disassemble a section of memory.
display	Print the value of an expression each time the program stops.
enable display	Enable one or more expressions that have been set to display when the program stops.
enable mem	Enable a memory region.
inspect	Same as print.
mem	Define attributes for a memory region.
output	Similar to print, but doesn’t save the value in history and doesn’t print a newline. For scripting.
print	Print the value of an expression.
print-object	Cause an Objective C object to print information about itself.
printf	Print values like the printf command.
ptype	Print the definition of a given type.
set	Evaluate an expression and save the result in a program variable.
set variable	Same as set, avoids conflict with GDB variables.
undisplay	Cancel one or more expressions that have been set to display when the program stops.
whatis	Print the data type of an expression.
x	Examine memory: x/ fmt address. See the entry for x in the later section "Alphabetical Summary of GDB Commands.”