Data - Debugging with GDB

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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.