Convenience variables¶
UDB provides a number of convenience variables to allow for easier
scripting. All of these variables have names starting _undo_.
The built-in command show convenience lists the convenience variables. For
example:
99% 234,515> show convenience
$_undo_time_max = 234567
$_undo_time_min = 1
$_undo_time = 234515
Available variables¶
$_undo_time_min¶
The bbcount of the earliest time in execution history. This value can never get smaller, but it can get larger when event log rotation occurs.
$_undo_time_max¶
The bbcount of the latest time in execution history.
that represents the end of time. Just like $_undo_time_min this value can
never get smaller, unlike $_undo_time_min this variable only gets larger
when the program is in record mode.
Example usage¶
The following example shows how to jump through execution history, ten BBs at a time, printing out the value at the top of the stack each time we jump backward.
99% 234,515> define rsp_every_ten
Type commands for definition of "rsp_every_ten".
End with a line saying just "end".
>while $_undo_time < $_undo_time_max - 10
>ugo time +10
>x $rsp
>end
>end
99% 234,515> rsp_every_ten
778 printf_fp.c: No such file or directory.
0x7fffffffd7f0: 0x00000000
142 mul.c: No such file or directory.
0x7fffffffd760: 0x0000000b
907 printf_fp.c: No such file or directory.
0x7fffffffd7f0: 0x00000000
957 in printf_fp.c
0x7fffffffd7c0: 0xf7e4f6a0
954 in printf_fp.c
0x7fffffffd7c0: 0xf7e4f6a0
