Changes to the adb command have been made to enable adb to handle 64-bit architectures in an improved manner.
The new version of the ADB debugger tool also provides better overall
performance and reliability, including improvements to command line
syntax and options, format strings, writing and searching, and expressions.
The ADB Debugger also supports the following new features:
Multiprocessor dump reading support
64-bit DLKM dump reading support
Support for all types of ELF and SOM object files
Single binary for 32-bit and 64-bit
The following discussion provides a summary of some of the
major changes to adb.
Specifying the New ADB Behavior |
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To specify the new adb command, use the -n command line option.
(For Itanium-based systems, the -n option
is the default). For example,
$ adb -n /stand/vmunix /dev/kmem
adb> runningprocs/d
runningprocs:
4
adb> q
$ |
There are no binary compatibility issues with this
change.
Retaining Old ADB Behavior |
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The only reason you should enable old adb behavior is to ensure that any scripts that were written
earlier run unchanged. For all interactive use and for new development
the old adb behavior is strongly discouraged.
If you wish, you can specify the old adb behavior on Itanium-based systems
by giving the -o command line option to adb.
Another way to enable old behavior is to add the following line
to the file $HOME/.adbrc.
Changes in ADB Command Line Syntax |
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The -k and -m command
line options are no longer required. If you wish to look at a crash
dump, you simply specify the crash dump directory as the sole argument.
(In previous versions of adb, the -k option was required
to recognize HP-UX crash dumps or /dev/mem. The -m option was required to recognize
multiple file HP-UX crash dumps.) In the backward compatibility
mode of operation of adb, the -k and -m options are
ignored with a warning.
ADB Command Prefix Changes |
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New adb commands no longer require a $ prefix
(as they did in previous versions of adb). The following examples
show the old syntax and the equivalent new syntax.
Example 7-1 To
quit adb
Old command: $q
New command: q
Example 7-2 To print the value of
a variable named q in hexadecimal:
Old command: q/X
New command: p q/x
ADB Command Processing |
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The new version of adb ignores the SIGQUIT signal.
However, on SIGINT signal adb interrupts the
current command and waits for the next command. An interrupted command
will not update any state variables. In this case, adb prints a
warning message.
adb exits on an EOF. EOL is
treated as a command with no command components and interpreted
accordingly.
ADB Changes to Format Strings |
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In the new version of adb, format characters make adb syntax
scalable and regular. All format characters are now lower case with
a preceding optional length specifier character.
printf Style Format Strings
The new adb also supports printf style format strings, which
should be preceded by a comma and enclosed within quotes. In this
case, the format characters and length specifiers are the same as
above, but flags, field widths and precision can be specified just
as for the printf() library function.
Changes in ADB Writing and Searching |
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The old adb uses the format characters w and W for
writing and l and L for searching.
However, the new adb uses characters w and l as
regular format characters. Therefore, in the new adb the following
replacements occur:
Table 7-3 Title not available (Changes in ADB Writing and Searching)
Old Format Character | Equivalent New Character |
|---|
w | =,2 |
W | = |
l | /,2 |
L | / |
Impact of Changes on Pre-Existing
ADB Scripts |
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The features or behaviors that are enabled in the backward
compatibility mode of adb (see “Retaining Old ADB Behavior”) are retained only for supporting macros written
for earlier versions of adb. No attempt is made to preserve the
interactive behavior as it will not affect macros. Users are discouraged
from using these features in new macros and scripts, as these features
may be obsoleted in a later version of adb. Most of the new features
introduced in this version of adb are not available in the backward
compatibility mode of operation of adb.
The features or behaviors described as deprecated (in the adb(1) manpage)
will be obsoleted over one or two major releases of the HP-UX operating
system. These features should not be used in new macros and scripts.
Most of these features and behaviors will have only minor impact on
existing macros or scripts. If there are any macros which use these features,
they should be rewritten before these are obsoleted.
ADB Documentation |
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The updated adb(1) manpage describes the new
and changed features of the ADB Debugger Tool in detail. For additional
information see the ADB Release Notes available
at http://docs.hp.com.
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