[ViewVC] Contents of: cebix/mon/README


  mon, Version 3.0
  A command-driven file monitor

  Copyright (C) 1997-2000 Christian Bauer, Marc Hellwig
  GNU binutils disassemblers (C) 1988, 89, 91, 93, 94, 95, 96, 97, 1998
    Free Software Foundation, Inc.


License
-------

mon is available under the terms of the GNU General Public License. See the
file "COPYING" that is included in the distribution for details.


Overview
--------

"mon" is an interactive command-driven file manipulation tool that is inspired
by the "Amiga Monitor" by Timo Rossi <trossi@jyu.fi>. It has commands and
features similar to a machine code monitor/debugger, but it is not intended
to be used for debugging. It doesn't operate on physical or virtual RAM
locations of a process but rather on a fixed-size (but adjustable) buffer with
adresses starting at 0. Also, there are no commands to trace code, set
breakpoints etc. There are, however, built-in PowerPC, 680x0, 80x86, 6502 and
8080 disassemblers.


Installation
------------

Please consult the file "INSTALL" for installation instructions.


Usage
-----

mon can be started from the Shell or from the Tracker (BeOS), but command line
history doesn't work when started from the Tracker). If you give no command
line arguments, mon enters interactive mode. Otherwise, all arguments are
interpreted and executed as mon commands. The default buffer size is 1MB.
The mon command prompt looks like this:

  [00000000]->

The number in brackets is the value of "." (the "current address", see the
section on expressions). You can get a short command overview by entering
"h".

Commands that create a longer output can be interrupted with Ctrl-C.

To quit mon, enter the command "x".


Constants, variables and expressions
------------------------------------

The default number base is hexadecimal. Decimal numbers must be prefixed with
"_". Hexadecimal numbers may also be prefixed with "$" for clarity. Numbers
can also be entered as ASCII characters enclosed in single quotes (e.g. 'BAPP'
is the same as $42415050). All numbers are 32-bit values (one word).

With the "set" command, variables can be defined that hold 32-bit integer
values. A variable is referred to by its name. Variable names may be arbitrary
combinations of digits and letters (they may also start with a digit) that
are not also valid hexadecimal numbers. Names are case-sensitive.

mon accepts expressions in all places where you have to specify a number. The
following operators are available and have the same meaning and precedence as
in the C programming language:

  ~   complement
  +   unary plus
  -   unary minus
  *   multiplication
  /   integer division
  %   modulo
  +   addition
  -   subtraction
  <<  shift left
  >>  shift right
  &   bitwise AND
  ^   bitwise exclusive OR
  |   bitwise inclusive OR

Parentheses may be used to change the evaluation order of sub-expressions.

There are two special symbols that can be used in expressions:

  .   represents the "current address" (the value of "." is also displayed in
      the command prompt). What exactly the current address is, depends on the
      command last executed. The display commands set "." to the address after
      the last address displayed, the "hunt" commands sets "." to the address
      of the first found occurence of the search string, etc.
  :   is used by the "apply" ("y") command and holds the value of the byte/
      half-word/word at the current address.

The "modify" (":"), "fill" ("f") and "hunt" ("h") commands require you to
specify a byte string. Byte strings consist of an arbitrary number of byte
values and ASCII strings separated by commas. Examples:

  "string"
  12,34,56,78,9a,bc,de,f0
  "this",0a,"is a string",0a,"with","newlines",_10


The buffer
----------

Those mon commands that operate on "memory" operate on a buffer allocated by
mon whose size is adjustable with the "@" command. The default buffer size is
1MB. The buffer is an array of bytes where each byte has a 32-bit integer
address. Addresses start at 0 and are taken modulo the buffer size (i.e. for
the default 1MB buffer, addresses 0 and 100000 refer to the same byte).

The buffer is the working area of mon where you load files into, manipulate
them, and write files back from. Arbitraty portions of the buffer may be used
as scratch space.


Commands
--------

The following commands are available in mon ('[]' marks a parameter than can be
left out):


  x                        Quit mon

quits mon and returns to the shell.


  h                        Show help text

displays a short overview of commands.


  ??                       Show list of commands

displays a short list of available commands.


  ver                      Show version

shows the version number of mon.


  ? expression             Calculate expression

displays the value of the given expression in hex, decimal, and ASCII
characters. If the value is negative, it is displayed as a signed and unsigned
number.


  @ [size]                 Reallocate buffer

changes the size of the buffer to the given number of bytes while preserving
the contents of the buffer. If the "size" argument is omitted, the current
buffer size is displayed.


  i [start [end]]          ASCII memory dump

displays the buffer contents from address "start" to address "end" as ASCII
characters. Entering "i" without arguments is equivalent to "i .". The value
of "." is set to the address after the last address displayed.


  b [start [end]]          Binary memory dump

displays the buffer contents from address "start" to address "end" in a binary
format. Entering "b" without arguments is equivalent to "b .". The value of
"." is set to the address after the last address displayed.


  m [start [end]]          Hex/ASCII memory dump

displays the buffer contents from address "start" to address "end" as hex
words and ASCII characters. Entering "m" without arguments is equivalent to
"m .". The value of "." is set to the address after the last address displayed.


  d [start [end]]          Disassemble PowerPC code

disassembles the buffer contents from address "start" to address "end".
Entering "d" without arguments is equivalent to "d .". The value of "." is
set to the address after the last address displayed.


  d65 [start [end]]        Disassemble 6502 code

disassembles the buffer contents from address "start" to address "end".
Entering "d65" without arguments is equivalent to "d65 .". The value of
"." is set to the address after the last address displayed.


  d68 [start [end]]        Disassemble 680x0 code

disassembles the buffer contents from address "start" to address "end".
Entering "d68" without arguments is equivalent to "d68 .". The value of
"." is set to the address after the last address displayed.


  d80 [start [end]]        Disassemble 8080 code

disassembles the buffer contents from address "start" to address "end".
Entering "d80" without arguments is equivalent to "d80 .". The value of
"." is set to the address after the last address displayed.


  d86 [start [end]]        Disassemble 80x86 code

disassembles the buffer contents from address "start" to address "end".
Entering "d86" without arguments is equivalent to "d86 .". The value of
"." is set to the address after the last address displayed.


  : start string           Modify memory

puts the specified byte string at the address "start" into the buffer. The
value of "." is set to the address after the last address modified.


  f start end string       Fill memory

fill the buffer in the range from "start" to (and including) "end" with the
given byte string.


  y[b|h|w] start end expr  Apply expression to memory

works like the "fill" ("f") command, but it doesn't fill with a byte string
but with the value of an expression that is re-evaluated for each buffer
location to be filled. The command comes in three flavors: "y"/"yb" works on
bytes (8-bit), "yh" on half-words (16-bit) and "yw" on words (32-bit). The
value of "." is the current address to be modified,  the value of ":" holds
the contents of this address before modification.

Examples:
  yw 0 fff :<<8    shifts all words in the address range 0..fff to the left
                   by 8 bits (you can use this to convert bitmap data from
                   ARGB to RGBA format, for example)
  y 0 1234 ~:      inverts all bytes in the address range 0..1234
  yh 2 ff 20000/.  creates a table of the fractional parts of the reciprocals
                   of 1..7f


  t start end dest         Transfer memory

transfers the buffer contents from "start" to (and including) "end" to "dest".
Source and destination may overlap.


  c start end dest         Compare memory

compares the buffer contents in the range from "start" to (and including)
"end" with the contents at "dest". The addresses of all different bytes and
the total number of differences (decimal) are printed.


  h start end string       Search for byte string

searches for the given byte string in the buffer starting at "start" up to
(and including) "end". The addresses and the total number of occurrences are
displayed. The value of "." is set to the address of the first occurrence. 


  \ "command"              Execute shell command

executes the given shell command which must be enclosed in quotes.


  ls [args]                List directory contents

works as the shell command "ls".


  rm [args]                Remove file(s)

works as the shell command "rm".


  cp [args]                Copy file(s)

works as the shell command "cp".


  mv [args]                Move file(s)

works as the shell command "mv".


  cd directory             Change current directory

works as the shell command "cd". The name of the directory doesn't have to be
enclosed in quotes.


  o ["file"]               Redirect output

When a file name is specified, all following output is redirected to this
file. The file name must be enclosed in quotation marks even if it contains
no spaces. Entering "o" without parameters closes the file and directs the
output into the terminal window again.


  [ start "file"           Load data from file

loads the contents of the specified file into the buffer starting from address
"start". The file name must be enclosed in quotation marks even if it contains
no spaces. The value of "." is set to the address after the last address
affected by the load.


  ] start size "file"      Save data to file

writes "size" number of bytes of the buffer from "start" to the specified file.
The file name must be enclosed in quotation marks even if it contains no spaces.


  set [var[=value]]        Set/clear/show variables

If no arguments are given, all currently defined variables are displayed.
Otherwise, the value of "var" is set to the specified value. If "=value"
is omitted, the variable "var" is cleared.


  cv                       Clear all variables

clears all currently defined variables.


rmon
----

When mon is started as "rmon", it enters "real mode". That is, all memory
related functions no longer operate on the buffer but on "real" (virtual)
memory. Unless you are writing Mac emulators, this is probably of not much
use. :-)


Examples
--------

Here are some simple examples for what is possible with mon.

Join "file1" and "file2" to "file3":

  [ 0 "file1"
  [ . "file2"
  ] 0 . "file3"

Remove the first 24 bytes (e.g. an unneeded header) of a file:

  [ 0 "file"
  ] 18 .-18 "file"

Load the mon executable and search for PowerPC "nop" commands:

  [ 0 "mon"
  h 0 . 60,00,00,00

Create a modified version of mon so that the prompt has " $" instead of "->":

  [ 0 "mon"
  set size=.
  h 0 . "->"
  : . " $"
  ] 0 size "mon1"

Convert a binary file which contains 16-bit numbers in little-endian format
to big-endian format (or vice-versa):

  [ 0 "file"
  yh 0 .-1 :>>8|:<<8  
  ] 0 . "file"

Load a BeBox boot ROM image and start disassembling the system reset handler:

  [ 0 "bootnub.image"
  d 100


History
-------

Please consult the file "ChangeLog" for the release history.


Christian Bauer
<Christian.Bauer@uni-mainz.de>

Marc Hellwig
<Marc.Hellwig@uni-mainz.de>
Revision:	1.4
Committed:	2000-09-25T12:44:30Z (24 years, 2 months ago) by cebix
Branch:	MAIN
Changes since 1.3:	+11 -10 lines
Log Message:	- replaced 680x0 and 80x86 disassemblers with the ones from GNU binutils - 680x0 disassembler shows symbolic MacOS low memory globals
#	Content
1
2	mon, Version 3.0
3	A command-driven file monitor
4
5	Copyright (C) 1997-2000 Christian Bauer, Marc Hellwig
6	GNU binutils disassemblers (C) 1988, 89, 91, 93, 94, 95, 96, 97, 1998
7	Free Software Foundation, Inc.
8
9
10	License
11	-------
12
13	mon is available under the terms of the GNU General Public License. See the
14	file "COPYING" that is included in the distribution for details.
15
16
17	Overview
18	--------
19
20	"mon" is an interactive command-driven file manipulation tool that is inspired
21	by the "Amiga Monitor" by Timo Rossi <trossi@jyu.fi>. It has commands and
22	features similar to a machine code monitor/debugger, but it is not intended
23	to be used for debugging. It doesn't operate on physical or virtual RAM
24	locations of a process but rather on a fixed-size (but adjustable) buffer with
25	adresses starting at 0. Also, there are no commands to trace code, set
26	breakpoints etc. There are, however, built-in PowerPC, 680x0, 80x86, 6502 and
27	8080 disassemblers.
28
29
30	Installation
31	------------
32
33	Please consult the file "INSTALL" for installation instructions.
34
35
36	Usage
37	-----
38
39	mon can be started from the Shell or from the Tracker (BeOS), but command line
40	history doesn't work when started from the Tracker). If you give no command
41	line arguments, mon enters interactive mode. Otherwise, all arguments are
42	interpreted and executed as mon commands. The default buffer size is 1MB.
43	The mon command prompt looks like this:
44
45	[00000000]->
46
47	The number in brackets is the value of "." (the "current address", see the
48	section on expressions). You can get a short command overview by entering
49	"h".
50
51	Commands that create a longer output can be interrupted with Ctrl-C.
52
53	To quit mon, enter the command "x".
54
55
56	Constants, variables and expressions
57	------------------------------------
58
59	The default number base is hexadecimal. Decimal numbers must be prefixed with
60	"_". Hexadecimal numbers may also be prefixed with "$" for clarity. Numbers
61	can also be entered as ASCII characters enclosed in single quotes (e.g. 'BAPP'
62	is the same as $42415050). All numbers are 32-bit values (one word).
63
64	With the "set" command, variables can be defined that hold 32-bit integer
65	values. A variable is referred to by its name. Variable names may be arbitrary
66	combinations of digits and letters (they may also start with a digit) that
67	are not also valid hexadecimal numbers. Names are case-sensitive.
68
69	mon accepts expressions in all places where you have to specify a number. The
70	following operators are available and have the same meaning and precedence as
71	in the C programming language:
72
73	~ complement
74	+ unary plus
75	- unary minus
76	* multiplication
77	/ integer division
78	% modulo
79	+ addition
80	- subtraction
81	<< shift left
82	>> shift right
83	& bitwise AND
84	^ bitwise exclusive OR
85	\| bitwise inclusive OR
86
87	Parentheses may be used to change the evaluation order of sub-expressions.
88
89	There are two special symbols that can be used in expressions:
90
91	. represents the "current address" (the value of "." is also displayed in
92	the command prompt). What exactly the current address is, depends on the
93	command last executed. The display commands set "." to the address after
94	the last address displayed, the "hunt" commands sets "." to the address
95	of the first found occurence of the search string, etc.
96	: is used by the "apply" ("y") command and holds the value of the byte/
97	half-word/word at the current address.
98
99	The "modify" (":"), "fill" ("f") and "hunt" ("h") commands require you to
100	specify a byte string. Byte strings consist of an arbitrary number of byte
101	values and ASCII strings separated by commas. Examples:
102
103	"string"
104	12,34,56,78,9a,bc,de,f0
105	"this",0a,"is a string",0a,"with","newlines",_10
106
107
108	The buffer
109	----------
110
111	Those mon commands that operate on "memory" operate on a buffer allocated by
112	mon whose size is adjustable with the "@" command. The default buffer size is
113	1MB. The buffer is an array of bytes where each byte has a 32-bit integer
114	address. Addresses start at 0 and are taken modulo the buffer size (i.e. for
115	the default 1MB buffer, addresses 0 and 100000 refer to the same byte).
116
117	The buffer is the working area of mon where you load files into, manipulate
118	them, and write files back from. Arbitraty portions of the buffer may be used
119	as scratch space.
120
121
122	Commands
123	--------
124
125	The following commands are available in mon ('[]' marks a parameter than can be
126	left out):
127
128
129	x Quit mon
130
131	quits mon and returns to the shell.
132
133
134	h Show help text
135
136	displays a short overview of commands.
137
138
139	?? Show list of commands
140
141	displays a short list of available commands.
142
143
144	ver Show version
145
146	shows the version number of mon.
147
148
149	? expression Calculate expression
150
151	displays the value of the given expression in hex, decimal, and ASCII
152	characters. If the value is negative, it is displayed as a signed and unsigned
153	number.
154
155
156	@ [size] Reallocate buffer
157
158	changes the size of the buffer to the given number of bytes while preserving
159	the contents of the buffer. If the "size" argument is omitted, the current
160	buffer size is displayed.
161
162
163	i [start [end]] ASCII memory dump
164
165	displays the buffer contents from address "start" to address "end" as ASCII
166	characters. Entering "i" without arguments is equivalent to "i .". The value
167	of "." is set to the address after the last address displayed.
168
169
170	b [start [end]] Binary memory dump
171
172	displays the buffer contents from address "start" to address "end" in a binary
173	format. Entering "b" without arguments is equivalent to "b .". The value of
174	"." is set to the address after the last address displayed.
175
176
177	m [start [end]] Hex/ASCII memory dump
178
179	displays the buffer contents from address "start" to address "end" as hex
180	words and ASCII characters. Entering "m" without arguments is equivalent to
181	"m .". The value of "." is set to the address after the last address displayed.
182
183
184	d [start [end]] Disassemble PowerPC code
185
186	disassembles the buffer contents from address "start" to address "end".
187	Entering "d" without arguments is equivalent to "d .". The value of "." is
188	set to the address after the last address displayed.
189
190
191	d65 [start [end]] Disassemble 6502 code
192
193	disassembles the buffer contents from address "start" to address "end".
194	Entering "d65" without arguments is equivalent to "d65 .". The value of
195	"." is set to the address after the last address displayed.
196
197
198	d68 [start [end]] Disassemble 680x0 code
199
200	disassembles the buffer contents from address "start" to address "end".
201	Entering "d68" without arguments is equivalent to "d68 .". The value of
202	"." is set to the address after the last address displayed.
203
204
205	d80 [start [end]] Disassemble 8080 code
206
207	disassembles the buffer contents from address "start" to address "end".
208	Entering "d80" without arguments is equivalent to "d80 .". The value of
209	"." is set to the address after the last address displayed.
210
211
212	d86 [start [end]] Disassemble 80x86 code
213
214	disassembles the buffer contents from address "start" to address "end".
215	Entering "d86" without arguments is equivalent to "d86 .". The value of
216	"." is set to the address after the last address displayed.
217
218
219	: start string Modify memory
220
221	puts the specified byte string at the address "start" into the buffer. The
222	value of "." is set to the address after the last address modified.
223
224
225	f start end string Fill memory
226
227	fill the buffer in the range from "start" to (and including) "end" with the
228	given byte string.
229
230
231	y[b\|h\|w] start end expr Apply expression to memory
232
233	works like the "fill" ("f") command, but it doesn't fill with a byte string
234	but with the value of an expression that is re-evaluated for each buffer
235	location to be filled. The command comes in three flavors: "y"/"yb" works on
236	bytes (8-bit), "yh" on half-words (16-bit) and "yw" on words (32-bit). The
237	value of "." is the current address to be modified, the value of ":" holds
238	the contents of this address before modification.
239
240	Examples:
241	yw 0 fff :<<8 shifts all words in the address range 0..fff to the left
242	by 8 bits (you can use this to convert bitmap data from
243	ARGB to RGBA format, for example)
244	y 0 1234 ~: inverts all bytes in the address range 0..1234
245	yh 2 ff 20000/. creates a table of the fractional parts of the reciprocals
246	of 1..7f
247
248
249	t start end dest Transfer memory
250
251	transfers the buffer contents from "start" to (and including) "end" to "dest".
252	Source and destination may overlap.
253
254
255	c start end dest Compare memory
256
257	compares the buffer contents in the range from "start" to (and including)
258	"end" with the contents at "dest". The addresses of all different bytes and
259	the total number of differences (decimal) are printed.
260
261
262	h start end string Search for byte string
263
264	searches for the given byte string in the buffer starting at "start" up to
265	(and including) "end". The addresses and the total number of occurrences are
266	displayed. The value of "." is set to the address of the first occurrence.
267
268
269	\ "command" Execute shell command
270
271	executes the given shell command which must be enclosed in quotes.
272
273
274	ls [args] List directory contents
275
276	works as the shell command "ls".
277
278
279	rm [args] Remove file(s)
280
281	works as the shell command "rm".
282
283
284	cp [args] Copy file(s)
285
286	works as the shell command "cp".
287
288
289	mv [args] Move file(s)
290
291	works as the shell command "mv".
292
293
294	cd directory Change current directory
295
296	works as the shell command "cd". The name of the directory doesn't have to be
297	enclosed in quotes.
298
299
300	o ["file"] Redirect output
301
302	When a file name is specified, all following output is redirected to this
303	file. The file name must be enclosed in quotation marks even if it contains
304	no spaces. Entering "o" without parameters closes the file and directs the
305	output into the terminal window again.
306
307
308	[ start "file" Load data from file
309
310	loads the contents of the specified file into the buffer starting from address
311	"start". The file name must be enclosed in quotation marks even if it contains
312	no spaces. The value of "." is set to the address after the last address
313	affected by the load.
314
315
316	] start size "file" Save data to file
317
318	writes "size" number of bytes of the buffer from "start" to the specified file.
319	The file name must be enclosed in quotation marks even if it contains no spaces.
320
321
322	set [var[=value]] Set/clear/show variables
323
324	If no arguments are given, all currently defined variables are displayed.
325	Otherwise, the value of "var" is set to the specified value. If "=value"
326	is omitted, the variable "var" is cleared.
327
328
329	cv Clear all variables
330
331	clears all currently defined variables.
332
333
334	rmon
335	----
336
337	When mon is started as "rmon", it enters "real mode". That is, all memory
338	related functions no longer operate on the buffer but on "real" (virtual)
339	memory. Unless you are writing Mac emulators, this is probably of not much
340	use. :-)
341
342
343	Examples
344	--------
345
346	Here are some simple examples for what is possible with mon.
347
348	Join "file1" and "file2" to "file3":
349
350	[ 0 "file1"
351	[ . "file2"
352	] 0 . "file3"
353
354	Remove the first 24 bytes (e.g. an unneeded header) of a file:
355
356	[ 0 "file"
357	] 18 .-18 "file"
358
359	Load the mon executable and search for PowerPC "nop" commands:
360
361	[ 0 "mon"
362	h 0 . 60,00,00,00
363
364	Create a modified version of mon so that the prompt has " $" instead of "->":
365
366	[ 0 "mon"
367	set size=.
368	h 0 . "->"
369	: . " $"
370	] 0 size "mon1"
371
372	Convert a binary file which contains 16-bit numbers in little-endian format
373	to big-endian format (or vice-versa):
374
375	[ 0 "file"
376	yh 0 .-1 :>>8\|:<<8
377	] 0 . "file"
378
379	Load a BeBox boot ROM image and start disassembling the system reset handler:
380
381	[ 0 "bootnub.image"
382	d 100
383
384
385	History
386	-------
387
388	Please consult the file "ChangeLog" for the release history.
389
390
391	Christian Bauer
392	<Christian.Bauer@uni-mainz.de>
393
394	Marc Hellwig
395	<Marc.Hellwig@uni-mainz.de>