ADB(1) COMMAND REFERENCE ADB(1)
NAME
adb - debugger
SYNOPSIS
adb [-p prompt] [-w] [-Idir] [objfil [corfil]] [-k]
DESCRIPTION
Adb is a general purpose debugging program. It may be used
to examine files and to provide a controlled environment for
the execution of UTek programs.
Objfil is normally an executable program file, preferably
containing a symbol table; if not, then the symbolic
features of adb cannot be used although the file can still
be examined. The default for objfil is a.out. Corfil is
assumed to be a core image file produced after executing
objfil; the default for corfil is core .
Requests to adb are read from the standard input and
responses are to the standard output.
Adb ignores QUIT; INTERRUPT causes return to the next adb
command.
In general, requests to adb are of the form
[address] [, count] [command] [;]
If address is present then dot is set to address. Initially
dot is set to 0. For most commands count specifies how many
times the command will be executed. The default count is 1.
Address and count are expressions.
The interpretation of an address depends on the context it
is used in. If a subprocess is being debugged, then
addresses are interpreted in the usual way in the address
space of the subprocess.
EXPRESSIONS:
. The value of dot.
+ The value of dot incremented by the current
increment.
^ The value of dot decremented by the current
increment.
" The last address typed.
integer
A number. The prefixes 0o and 0O ("zero oh") force
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ADB(1) COMMAND REFERENCE ADB(1)
interpretation in octal radix; the prefixes 0t and 0T
force interpretation in decimal radix; the prefixes
0x and 0X force interpretation in hexadecimal radix.
Thus, 0o20 = 0t16 = 0x10 = sixteen. If no prefix
appears, then the default radix is used (see the $d
command.) The default radix is initially
hexadecimal. The hexadecimal digits are
0123456789abcdefABCDEF with the obvious values. Note
that a hexadecimal number whose most significant
digit would otherwise be an alphabetic character must
have a 0x (or 0X) prefix (or a leading zero if the
default radix is hexadecimal).
integer.fraction
A 32 bit floating point number. The radix must be set
to decimal.
'cccc' The ASCII value of up to four characters. The
backslash character (\) may be used to escape an
apostrophe character (').
< name The value of name, which is either a variable name or
a register name. Adb maintains a number of variables
(see VARIABLES) named by single letters or digits.
If name is a register name then the value of the
register is obtained from the system header in
corfil. The register names are those printed by the
$r command. Some special provisions have been made
for the names of the floating point registers on the
National 32000 fpu. If the register name is specified
starting with F (for example F0) it will be treated
as a double floating register pair (for reading and
writing). Entering the register name with an f (for
example f1) will cause it to be treated as a single
floating register.
symbol A symbol is a sequence of upper- or lowercase
letters, underscores, or digits, not starting with a
digit. The backslash (\) may be used to escape other
characters. The value of symbol is taken from the
symbol table in objfil. An initial underscore
character (_) will be prepended to symbol if needed.
_ symbol
In C, the true name of an external symbol begins with
an underscore (_) It may be necessary to utter this
name to distinguish it from internal or hidden
variables of a program.
routine.name
The address of the variable name in the specified C
routine. Both routine and name are symbols. If name
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ADB(1) COMMAND REFERENCE ADB(1)
is omitted the value is the address of the most
recently activated C stack frame corresponding to
routine.
(exp) The value of the expression exp.
Monadic operators:
*exp
The contents of the location addressed by exp in corfil.
@expThe contents of the location addressed by exp in objfil.
-exp
Integer negation.
~exp
Bitwise complement.
#exp
Logical negation.
Dyadic operators:
These are left associative and are less binding than monadic
operators.
e1+e2
Integer addition.
e1-e2
Integer subtraction.
e1*e2
Integer multiplication.
e1%e2
Integer division.
e1&e2
Bitwise conjunction.
e1|e2
Bitwise disjunction.
e1#e2
E1 rounded up to the next multiple of e2.
COMMANDS:
Most commands consist of a verb followed by a modifier or
list of modifiers. The following verbs are available (the
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ADB(1) COMMAND REFERENCE ADB(1)
commands ? and \ may be followed by *; see ADDRESSES for
further details):
?f Locations starting at address in objfil are printed
according to the format f. Dot is incremented by the
sum of the increments for each format letter (q.v.).
/f Locations starting at address in corfil are printed
according to the format f and dot is incremented as for
? (question mark).
=f The value of address itself is printed in the styles
indicated by the format f. (For i format, ? is printed
for the parts of the instruction that reference
subsequent words.)
A format consists of one or more characters that specify a
style of printing. Each format character may be preceded by
a decimal integer that is a repeat count for the format
character. While stepping through, a format dot is
incremented by the amount given for each format letter. If
no format is given then the last format is used. The format
letters available are as follows:
o 2 Print two bytes in octal. All octal numbers
output by adb are preceded by 0.
O 4 Print four bytes in octal.
q 2 Print in signed octal.
Q 4 Print long signed octal.
d 2 Print in decimal.
D 4 Print long decimal.
x 2 Print two bytes in hexadecimal.
X 4 Print four bytes in hexadecimal.
u 2 Print as an unsigned decimal number.
U 4 Print long unsigned decimal.
f 4 Print the 32 bit value as a floating point number.
F 8 Print double floating point.
g 4 Print the floating constant as a 32 bit hex
floating value.
G 8 Print the floating constant as a 64 bit hex double
floating value.
b 1 Print the addressed byte in octal.
c 1 Print the addressed character.
C 1 Print the addressed character using the standard
escape convention where control characters are
printed as <CTRL-X> and the delete character is
printed as <CTRL-?>
s n Print the addressed characters until a zero
character is reached.
S n Print a string using the <CTRL-X> escape
convention (see C above). The n is the length of
the string including its zero terminator.
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ADB(1) COMMAND REFERENCE ADB(1)
Y 4 Print four bytes in date format (see ctime(3c)).
i n Print as machine instructions. The n is the
number of bytes occupied by the instruction. This
style of printing causes variables 1 and 2 to be
set to the offset parts of the source and
destination respectively.
a 0 Print the value of dot in symbolic form. Symbols
are checked to ensure that they have an
appropriate type as indicated below:
/ Local or global data symbol.
? Local or global text symbol.
= Local or global absolute symbol.
p 4 Print the addressed value in symbolic form using
the same rules for symbol lookup as a.
t 0 When preceded by an integer, it tabs to the next
appropriate tab stop. For example, 8t moves to
the next eight-space tab stop.
r 0 Print a space.
n 0 Print a newline.
"..." 0
Print the enclosed string.
^ Dot is decremented by the current increment.
Nothing is printed.
+ Dot is incremented by 1. Nothing is printed.
- Dot is decremented by 1. Nothing is printed.
newline
Repeat the previous command with a count of 1.
[ ] Right and left square brackets. Set memory breakpoint
at address and break if the memory read/write has
occured. If r appears inside the brackets, as in [r],
then the memory breakpoint is set at the address
specified and the break occurs on a memory read. If w
appears inside the brackets, then the memory breakpoint
is set at the address and the break occurs on a memory
write. If d appears inside the brackets, then the
breakpoint (specified by address) is deleted.
[?/]l value mask
Words starting at dot are masked with mask and compared
with value until a match is found. If L is used then
the match is for four bytes at a time instead of two.
If no match is found then dot is unchanged; otherwise,
dot is set to the matched location. If mask is omitted
then -1 is used.
[?/]w value ...
Write the two-byte value into the addressed location.
If the command is W, write four bytes. Odd addresses
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ADB(1) COMMAND REFERENCE ADB(1)
are not allowed when writing to the subprocess address
space.
[?/]m b1 e1 f1[?/]
New values for (b1, e1, f1) are recorded. If less than
three expressions are given, then the remaining map
parameters are left unchanged. If the ? or / is
followed by * , then the second segment (b2,e2,f2) of
the mapping is changed. If the list is terminated by ?
or / then the file (objfil or corfil respectively) is
used for subsequent requests. For example, /m? will
cause / to refer to objfil.
>name
Dot is assigned to the variable or register named.
! A shell ( /bin/sh ) is called to read the rest of the
line following !.
$modifier
Miscellaneous commands. The available modifiers are:
<f Read commands from the file f. If this command is
executed in a file, further commands in the file
are not seen. If f is omitted, the current input
stream is terminated. If a count is given, and is
zero, the command will be ignored. The value of
the count will be placed in variable 9 before the
first command in f is executed.
<<f Similar to < except it can be used in a file of
commands without causing the file to be closed.
Variable 9 is saved during the execution of this
command, and restored when it completes. There is
a (small) finite limit to the number of << files
that can be open at once.
>f Append output to the file f, which is created if
it does not exist. If f is omitted, output is
returned to the terminal.
? Print process ID, the signal which causes stoppage
or termination, as well as the registers as $r.
This is the default if modifier is omitted.
r Print the general registers and the instruction
addressed by pc. Dot is set to pc.
b Print all breakpoints and their associated counts
and commands.
c C stack backtrace. If address is given then, it
is taken as the address of the current frame
instead of the contents of the frame-pointer
register. If count is given, then only the first
count frames are printed.
d Set the default radix to address and report the
new value. Note that address is interpreted in
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ADB(1) COMMAND REFERENCE ADB(1)
the (old) current radix. Thus 10$d never changes
the default radix. To make decimal the default
radix, use 0t10$d.
e The names and values of external variables are
printed.
w Set the page width for output to address (default
80).
s Set the limit for symbol matches to address
(default 255).
o All integers input are regarded as octal.
q Exit from adb.
v Print all nonzero variables in octal.
m Print the address map.
t Toggle the virtual to physical trace output. Only
useful if -k command line option is also
specified.
n Toggle the National-32000/Compiler disassembler
display format (default is National-32000).
:modifier
Manage a subprocess. Available modifiers are:
bc Set breakpoint at address. The breakpoint is
executed count-1 times before causing a stop.
Each time the breakpoint is encountered, the
command c is executed. If this command is omitted
or sets dot to zero, then the breakpoint causes a
stop.
d Delete breakpoint at address.
D Delete all breakpoints.
r Run objfil as a subprocess. If address is given
explicitly then the program is entered at this
point; otherwise the program is entered at its
standard entry point. Count specifies how many
breakpoints are to be ignored before stopping.
Arguments to the subprocess may be supplied on the
same line as the command. An argument starting
with < or > causes the standard input or output to
be established for the command.
cs The subprocess is continued with signal s (see
sigvec(2)). If address is given, then the
subprocess is continued at this address. If no
signal is specified, then the signal that caused
the subprocess to stop is sent. Breakpoint
skipping is the same as for r.
ss Same as for c except that the subprocess is single
stepped, count times. If there is no current
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ADB(1) COMMAND REFERENCE ADB(1)
subprocess, then objfil is run as a subprocess as
for r. In this case no signal can be sent; the
remainder of the line is treated as arguments to
the subprocess.
k The current subprocess, if any, is terminated.
ADDRESSES:
The address in a file, associated with a written address, is
determined by a mapping associated with that file. Each
mapping is represented by two triples -- (b1, e1, f1) and
(b2, e2, f2) -- and the filename address corresponding to a
written address is calculated as follows:
b1 < address < e1 => filename address = address +
f1-b1,
or
b2 < address < e2 => filename address = address + f2-b2
If not in this form, the requested address is not legal. In
some cases, such as for programs with separated I and D
space, the two segments for a file may overlap. If a ? or /
is followed by an * then only the second triple is used.
The initial setting of both mappings is suitable for normal
a.out and core files. If either file is not of the kind
expected, then, for that file, b1 is set to 0, e1 is set to
the maximum file size, and f1 is set to 0; in this way the
whole file can be examined with no address translation.
VARIABLES:
Adb provides a number of variables. Named variables are set
initially by adb but are not used subsequently. Numbered
variables are reserved for communication as follows:
0 The last value printed.
1 The last offset part of an instruction source.
2 The previous value of variable 1.
9 The count on the last $< or $<< command.
On entry, the following are set from the system header in
the corfil (if corfil does not appear to be a core file then
these values are set from objfil):
b The base address of the data segment.
d The data segment size.
e The entry point.
m The magic number (0407, 0410 or 0413).
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ADB(1) COMMAND REFERENCE ADB(1)
s The stack segment size.
t The text segment size.
OPTIONS
-p Makes adb interpret the following string as the prompt
to use when it is ready to accept commands from your
terminal.
-w Both objfil and corfil are created if necessary and
opened for reading and writing so that files can be
modified using adb.
-I Specifies a directory where files to be read with $< or
$<< (see below) will be sought; the default is
/usr/lib/adb.
-k Specifies that corfil represents physical memory of a
UTek kernel (either /dev/mem or the vmcore.? file
generated by savecore(8)). Enables virtual to physical
address translation when looking in corfil .
FILES
a.out Default binary filename.
core Default core image filename.
DIAGNOSTICS
adb This is given when there is no current command or
format.
This command comments about inaccessible files, syntax
errors, abnormal termination of commands, and so forth.
Exit status is 0, unless the last command failed or returned
nonzero status.
CAVEATS
Since no shell is invoked to interpret the arguments of the
:r command, the customary wild-card and variable expansions
cannot occur.
SEE ALSO
cc(1), sdb(1), ptrace(2), a.out(5), core(5), savecore(8).
Printed 10/17/86 9
%%index%%
na:72,50;
sy:122,223;
de:345,2120;2609,3123;5876,1517;7537,2748;10429,2986;13559,3063;16766,2775;19685,2445;22274,80;
op:22354,927;
fi:23281,168;
di:23449,383;
ca:23832,212;
se:24044,189;
%%index%%000000000221