? [option.]expr
? "string", expr, ...
The ? command evaluates an expression and displays the result.
Option | Format |
---|---|
h | Hexadecimal |
d | Decimal |
t | Decimal |
o | Octal |
q | Octal |
y | Binary |
By default, the command displays all formats: decimal, hexadecimal, octal, binary, ASCII, and Boolean.
String | Description |
---|---|
%% | Displays a percent sign (%). |
%A | Displays matching expr as an address. |
%b | Displays matching expr in binary format. |
%c | Displays matching expr as a character. |
%d | Displays matching expr in decimal format. |
%G | Evaluates matching expr as an address and displays the group and symbol associated with the address in group:symbol format. |
%M | Evaluates matching expr as an address and displays the map file, group and symbol associated with the address in map:group:symbol format. |
%o | Displays matching expr in octal format. |
%S | Evaluates matching expr as an address and displays the map file, group and symbol associated with the address. |
%s | Evaluates matching expr as an address and displays the string at that address. |
%u | Displays matching expr in unsigned decimal format. |
%X | Displays matching expr in hexadecimal format. |
%x | Displays matching expr in hexadecimal format |
\a | Inserts a bell (alert) character. |
\b | Inserts a backspace character. |
\n | Inserts a new line character. |
\r | Inserts a carriage return character. |
\t | Inserts a horizontal tab character. |
One expression must be given for each formatting descriptor in the string. Multiple expressions can be separated with commas (,) or spaces.
Formatting descriptors can have these optional prefixes:
Prefix | Description |
---|---|
A | [-][width][.precision][a][p][n][L][H][N] |
b | [-][0][width][.precision][p][n] |
d | [-][+][ ][0][width][.precision][p][n] |
G | [-][width][.precision][a][p][n][L][H][N] |
M | [-][width][.precision][a][p][n][L][H][N] |
o | [-][0][width][.precision][p][n] |
s | [-][width][.precision][a] |
S | [-][width][.precision][a][p][n][L][H][N] |
u | [-][0][width][.precision][p][n] |
X | [-][#][0][width][.precision][p][n] |
x | [-][#][0][width][.precision][p][n] |
Specifying an asterisk (*) for the width or precision parameter causes the field width or precision, respectively, to be picked up from the next parameter. Decimal values can also be specified for the width and precision parameters. The prefix letters have these meanings:
Prefix | Description |
---|---|
a | Address argument size |
H | Display 16-bit offset |
L | Display 32-bit offset |
N | Display offset only |
p | Get the previous symbol, symbol address, or offset |
n | Get the next symbol, symbol address, or offset |