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10 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 Using gdb with Different Languages). It may also print the expression using a Python-based pretty-printer (see Pretty Printing).

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 Examining 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 Examining the Symbol Table.