RTEMS GNU Tools On-Line Library

Data

Debugging with GDB

Chapter 8: Examining Data

The usual way to examine data in your program is with the print command (abbreviated p), or its synonym inspect. It evaluates and prints the value of an expression of the language your program is written in (see Languages).

print expr
print /f expr: expr is an expression (in the source language). By default the value of expr is printed in a format appropriate to its data type; you can choose a different format by specifying `/f', where f is a letter specifying the format; see Output Formats.
print
print /f: If you omit expr, GDB displays the last value again (from the value history; see Value History). This allows you to conveniently inspect the same value in an alternative format.

A more low-level way of examining data is with the x command. It examines data in memory at a specified address and prints it in a specified format. See Memory.

If you are interested in information about types, or about how the fields of a struct or a class are declared, use the ptype exp command rather than print. See Symbols.

Expressions Expressions

Variables Program variables

Arrays Artificial arrays

Output Formats Output formats

Memory Examining memory

Auto Display Automatic display

Print Settings Print settings

Value History Value history

Convenience Vars Convenience variables

Registers Registers

Floating Point Hardware Floating point hardware

Debugging with GDB