I have a command that essentially functions like clearing the memory, but doesn't wipe programs and sets the settings I like. I found out that while it does its job well, it doesn't seem to clear the equations in the Y= menu. Is there a command or another way to achieve this?
PROGRAM:CLEAR
:MATHPRINT
:Normal
...
:DiagnosticOn
:ClrDraw
:Clear Entries
:ClrAllLists
:SetUpEditor
:ClrHome
:"
On a similar note to TimTech, Delvar can be used to reset the value of a variable.
DelVar Y1
The benefit of this is that multiple DelVar calls can be chained without a line break.
DelVar Y1DelVar Y2Disp "Done
A non-programmatic way of clearing a calculator is to use the key sequence 2nd + 7 1 2. Unfortunately, this also clears programs.
This method will clear all RAM on the calculator, so use it with caution.
I found a better programmatic way of clearing the Y-VARS. This method also resets all other graph settings to their default value. In your case, this seems to be a desirable side-effect. Unfortunately, it requires a little bit of set up and occupies one of the Graph Database variables (119 Bytes). Because this variable can be kept archived, this does not consume any RAM.
Setup
Manually clear All Y-VARS, including parametric, polar and sequence variables.
Manually Reset All graph window settings to their default
ZStandard
RectGC
CoordOn
GridOff
AxesOn
LabelOff
ExprOn
Store current setting in a Graph Database variable
StoreGDB GDB1 entered with key strokes: 2ndPRGMâ—„5VARS3ENTERENTER
Archive GDB1
Archive GDB1 entered with keystrokes: 2nd+5VARS3ENTERENTER
Use in Program
To use this archived variable in a program, you must unarchive it, recall its contents, and finally archive the variable again. This is accomplished by the following code block.
UnArchive GDB1
RecallGDB GDB1
Archive GDB1
If you're using a TI-83 calculator, you need to skip the steps involving archiving because the TI-83 does not support flash memory. The TI-83 Plus and above work fine, however.
No command, but you can do "->Y1 or DelVar Y1 to clear Y1, and similarly for the others.
Related
I am trying to allow others to use my programs, but I don't want those users to be sharing the programs without my permission, so my goal is to prevent the users from doing this on the TI-84 calculator, but I have had no apparent luck.
For the TI-84 calculator, I have tried the getkey command and the stop. I have tried conditional statements with for and while loops, but I can't seem to prevent the user from sharing the code.
Prompt V
V+2 -> C
Disp C
The code works like it is intended but I can't prevent people from transferring this code to other calculators.
There is no way to prevent people from transferring programs over the calculator. What you could try to do is make it so that after you transfer the program yourself you store a password into a variable that they are unlikely to use (done manually, make sure to clear afterwards). When the program runs it checks if the variable stores the correct value. If someone else transfers the program and doesn't load the password into the correct variable, then the program won't work. However, they can figure this out by simply reading the code. If you want to be extra tricky, you can create a simple hashing algorithm and read from multiple variables. For instance, storing 123 in Z could be hashed by *28 + 54 mod 71 to get to 19. Apply those math functions to the chosen variables and then compare to their hashed value. This protects people from figuring out the password by checking the program (since 19 cannot be reversed to 123). Of course, they can just delete the check, so try to hide it somewhere among junk code. Now, they might overwrite those variables where your password is stored (often by running other programs that use those variables). Simply tell them that they have to come back to you so you can "fix" their program. Hope this helps.
I have been facing this problem for sometimes now, a laziness caused in part by the fact that Microsoft Office automatically save files you are working on with versions and automatic recovery.
Many times when I am starting a new notebook in mathematica to do some tests or whatever, I often forget to save what I am doing.
Every now and then, depending on the computer I am using, the computer crashes and all the beautiful work I was doing is lost forever...
Is there a way to get around this other that manically saving my files every five minutes? How about file versioning?
BTW: Using MMA V8
Regarding autosaving, you may want to check out the NotebookAutoSave option, which can be set to True through Fromat->Option Inspector. You have to choose "Selected notebook", then go to Notebook Options -> File Options, and set NotebookAutoSave to True. Then, your notebook will be saved after every evaluation. Whether or not this is a satisfactory solution, of course depends on the situation.
But my experience is that the most reliable way is to develop a CTRL+S reflex - this one never lets me down and is working quite well.
As for the versioning, it is much easier with packages, for which you can use WorkBench which has integrated support for CVS and support for SVN via Eclipse plugin. For notebooks, I refer you to this SO thread. You may also find this Mathgroup discussion of some interest.
EDIT
For M8, for auto-saving purposes you can probably also run
RunScheduledTask[NotebookSave[EvaluationNotebook[]],{300}]
But I can not test this code at the moment
EDIT2
I just came across this post in the Toolbag repository - which may also be an alternative for the autosave part of the question (but please see also the discussion in comments on the relative advantages of scheduled tasks vs. Dynamic)
Since you have MMA version 8 you could use:
saveTask = CreateScheduledTask[FrontEndExecute[FrontEndToken["Save"]], 5*60];
StartScheduledTask[saveTask];
to save every 5 minutes (change the term 5*60 for other timings).
To remove the auto-save task use:
RemoveScheduledTask[saveTask];
To save only a fixed, specific notebook, store its handle in nb (finding it using Notebooks, SelectedNotebook, InputNotebook or EvaluationNotebook) and use FrontEndToken[nb,"Save"] instead of just FrontEndToken["Save"]
I have a Mathematica package that provides auto-backup functionality. When enabled, the current notebook--call it "blah.nb"--will be backed up to "blah.nb~" after a configurable amount of time has elapsed. I use it constantly and it has saved me from losing work many, many times. It's better than autosaving since it doesn't touch the actual notebook file: if you screw something up or something gets corrupted you don't want to overwrite your main file. :)
It's on GitHub here.
I've got an autosave routine that saves a copy of every open, modified notebook every 5 minutes (or whatever interval you prefer. It leaves your manually-saved copy alone, and saves a "swap file" in a separate directory that can be easily recovered if need be. The code (to be copied to init.m) is given in this answer: https://mathematica.stackexchange.com/questions/18380/automatic-recovery-after-crash/65852#65852, and copied below:
Motivated by the same concerns, I wrote the following code and added it to my init.m file. There are two main entries you'll want to change to use this. The global variable $SwapDirectory is where the swap files are saved (by swap file, I mean it in the VIm sense; an "extra" copy of your notebook, separate from your manually saved copy that periodically saves any new work). The swap files are organized within the swap directory in a directory structure which "mirrors" their original file locations, and have ".swp" appended to their file names. The other variable you might want to change is the number of seconds between autosaves, indicated by the "300" (corresponding to 5 minutes) near the bottom of the code below. At the appropriate times, this code will (automatically in the background) save swap files for ALL open notebooks, unless they are unmodified from their manually-saved versions (this exception makes the code more efficient, and more importantly, prevents the storage of swap files for documentation notebooks, for example).
In its current form, the code does not filter for only the input cells, but hopefully you can use the other answers to make that modification yourself.
Some things to note:
1) the Mathematica Put command seems to have trouble writing to network drives, even when offline access is enabled. Therefore, it is probably best to choose a SwapDirectory that is on your local machine.
2) Within SwapDirectory, you should create a sub-directory called "Recovery". This is where the AutoSaveSwap routine will make an initial save of any notebooks for which there is NO existing manual save location.
3) Simply evaluate
RecoverSwap["filePath"]
where "filePath" is a string representing the filePath of the MANUALLY-SAVED copy of the file (i.e., not the file that was created by AutoSave). This will then pop up a window containing the most recent auto-saved version of the file. The manually saved version is NEVER overwritten, unless you explicitly choose to do so. Once the recovered version pops up, you can save it whereever you like, or discard it at your discretion.
4) You should probably add this code to the KERNEL version of init.m ($UserBaseDirectory/Kernel/init.m) rather than the frontend version... this way, if you quit and restart the kernel, the autosave feature will also restart. On the other hand, this means that you must evaluate at least one expression after each start or restart to begin auto-saving. Once this initial evaluation is done, you do NOT need to have evaluated a cell for it to be backed up (unlike the built-in autosave utility).
Hope this helps someone! Feel free to respond with any questions, suggestions, or requests for improvement you may have. And, if you find this post useful, upvotes would be most appeciated! Take care.
$SwapDirectory= "C:\\Users\\pacoj\\Swap Files\\";
SaveSwap[nb_NotebookObject]:=Module[
{fileName, swapFileName, nbout, nbdir, nbdirout, recoveryDir},
If[ ! SameQ[Quiet[NotebookFileName[nb]], $Failed],
(* if the notebook is already saved to the file system *)
fileName = Last[ FileNameSplit[ NotebookFileName[nb]] ];
swapFileName = fileName <> ".swp";
nbdir = Rest[FileNameSplit # NotebookDirectory[nb]];
nbdirout= FileNameJoin[ FileNameSplit[$SwapDirectory]~Join~nbdir]<>"\\";
If[!DirectoryQ[nbdirout], CreateDirectory[nbdirout]];
nbout = NotebookGet[nb];
Put[nbout, nbdirout <> swapFileName],
(* else, if the file has never been saved, save as untitled *)
recoveryDir= $SwapDirectory <> "Recovery\\\";
fileName= ("WindowTitle" /. NotebookInformation[nb])<>".nb";
NotebookSave[nb, recoveryDir <> fileName]
]
];
RecoverSwap::noswp= "swap file `1` not found in expected location";
RecoverSwap[nbfilename_String]:=Module[
{fileName, swapFileName, nbin, nbdir, nbdirout},
fileName= Last[ FileNameSplit[ nbfilename] ];
swapFileName= fileName <> ".swp";
nbdir= Most[ Rest[FileNameSplit # nbfilename] ];
nbdirout= FileNameJoin[ FileNameSplit[$SwapDirectory]~Join~nbdir]<>"\\\";
If[ FileNames[swapFileName, {nbdirout}] == {},
Message[RecoverSwap::noswp,nbdirout <> swapFileName]; Return[],
nbin= Get[nbdirout <> swapFileName]; NotebookPut[nbin]
]
];
AutoSaveSwaps= CreateScheduledTask[
SaveSwap /# Select[Notebooks[], "ModifiedInMemory" /. NotebookInformation[#]&],
300
]
StartScheduledTask[AutoSaveSwaps]
I have to find a button's name in a running process memory in Mac OSX and change it.
Supposing there is a "Test" application where it has a "Hello" button, is there any way to attach to "Test" application and change the "Hello!" button to "Bye!"?
I assume this could be done either using GDB or Xcode. If not, how can I do this?
Edit
Assuming you are really looking for dynamic data (as opposed to what your sample seemed to suggest :)) you could always just work with the debugger commands. This will require you to have a sense of the possible memory range to scan (or you'll simply get useless memory violations):
Use gdb commands, loop constructs and libc functions
# assume 0x1234 is a likely base address, say for the heap
(gdb) set $x=0x1234
(gdb) set $y = strdup("lookforthistext")
(gdb) while(0!=memcmp($x++, $y, 15) && $x<0x4321)
>end
(gdb) p $x
(gdb) x $x
This example scans the region 0x1234...0x4321 for the first match and prints/examines the output address.
You can use similar tricks (strncpy...?) to overwrite the memory if you had access to it.
Of course the program may fail dramatically if you do things like changing the length of a substring.. YMMV).
Consider saving your concocted commands as a script (turn on logging, use .gdbinit or even create gdb functions; sadly I know little about the latter)
Original answer:
You "need to"? I doubt it. Your best bet is to work with the windowing/UI API's of your operating system to retrieve the actual window that display the text and make it display another text (usually by sending it appropriate control messages). You'll need plenty of COW powers (think: root) to pull that off.
To answer the direct question:
Usually, messages like this are constants (static data) and as such are either
present in the data segment
read (memory mapped pages) from resources
Both of which are usually (these days at least) in read-only memory segments (think of sharing of memory mapped pages; this gives the kernel opportunity to share mapped regions of shared binary objects between processes - also it serves the obvious security purposes).
On the upside,
strings myprogram | grep 'Hello"
will tell you whether you can use sed, a hex editor or any other suitable editor to manipulate the binary even before it starts. There are two drawbacks I can think of here:
it is not dynamic (you can't have the text change on the fly)
it may break code signing (meaning the executable might get rejected by the OS because it has been modified).
To restrict the scope, let assume we are in Windows world only.
Also assume we don't want to play with permission policy.
Is it possible for us to create a file that cannot be copied?
Thank you in advance.
"Trying to make digital files uncopyable is like trying to make water not wet." ~ Bruce Schneier
No. You can't create a file that a SYSADMIN can't copy. You could encrypt it, though.
Well, how about creating a file that uses up more than 50% of the total space on that machine and that is not compressible?
For instance, let us assume that you want to save a boolean (true or false) in such a fashion.
Depending on its value, you could then write a bit stream of ones or zeroes and encrypt said stream using some kind of encryption algorith, such as AES in CBC mode. This gives you the added advantage of error correction. Even in case of massive data corruption, you should be able to recover your boolean by checking whether ones or zeroes are prevalent in the decrypted stream.
In that case you cannot copy it around (completely) on the machine...
Of course, any type of external memory that can be added to the system would pose a problem in this scenario. But the file would be already encrypted, so don't worry about it too much...
Any file that can be read can have its contents written to another location (such as another file, i.e. copied).
The only thing you can do is limit who/what can read the file.
What is the motivation behind? If it is a read-only file, you can have it as embedded resources within your assembly.
Nice try, RIAA.
But seriously, no you can not. It is always possible to copy, you can just make it it more difficult for people to make sense of the file or try to hide it using like encryption. Spotify does it.
If you really try hard thou, you cold make a root-kit for windows and use it to prevent windows from even knowing about the file and also prevent copies. The file will still be there and copy-able by other tools, or Linux accessing the ntfs.
If in a running process you open a file and hold an exclusive lock, then other processes cannot read the file until you close the handle or your process terminates. However, as admin you could forcibly remove the lock handle.
Short answer: No.
You can, of course, use security settings to limit who can read the file. But if someone can read it, then they can copy it. Even if you found some operating system trick to disable "ordinary" copying, if someone can read the file, they can extract the contents, store it in memory, and then write it somewhere else.
You can encrypt the contents so it's only useful to your own program, that knows how to decrypt it.
That's about it.
When using Windows 7 to copy some files from a hard drive, certain files popped up a message saying they could not be copied in their entirety; certain data would be omitted from the copy. I suspect that had something to do with slack space at the end of the files, though I thought the message was curious. I would have expected the copy operation to just ignore the slack space.
If you are running old (OLD) versions of windows, there are certain characters you can put in the filename that make it invalid, not listed in folders, etc. They were used a lot in the old pub ftp days of filesharing ;)
In the old DOS days, you used to be able to flag disk sectors as bad and still read from them. This meant the OS ignored the sector in question but your application would know where to look and be able to get the data. Not sure this would work these days.
Another old MS-DOS trick was to put a space character in the middle of the filename (yes, spaces were valid characters for filenames). Since there was no method on the command line to escape a space, the file couldn't be copied using the DOS commands.
This answer is outside Windows so yeah
Dont know if its already been said but what about a file that is an inseperable part of the firmware so that it is always on AND running, perhaps it has firmware that generates a sequence that is required for the other . AN incedental effect of its running is to prevent any 80% or more of its code from being replicated. Lets say its on an entirely different board, protected by surge protectors, heavy em proof shielding and anything else required to make it completely unerasable.
If its possible to make a program that is ALWAYS on and running as long as the copying software is running then yes.
I have another way and this IS with windows. I will come to your house and give you a disk, i will then proceed to destroy every single computer you put the disk into. This doesnt work on XP
Well technically you could create and write to a write-only network share.
i have found myself several times in the need of knowing the last values set to a range of variables that were in a certain portion of code, or method; maybe dispersed around the program.
does anyone know a way to select variables and know the last value set to them after the program ends running - in a windows maybe ?
There isn't anything I know of that will record every value ever assigned to every variable in your program in case you want to look at it later. It is possible with VS2010's historical debugging abilities to look at "values from the past" although I haven't used this yet, so I don't know if that ability extends "beyond death" of the process.
You may also be able to use tracepoints (VS2008 and later). These are like breakpoints, but instead of stopping execution they simply print information to the debug output. So you could add a tracepoint for a variable so that each time it is changed its value is reported (basically the same as printing the values out in your code, but you don't have to change your code to enable them, and can add them while your code is executing).
Two simple approaches that will work for pretty much any dev environment are:
Write the values to an application log each time they change, then read the last reported entries. If you realise you need 5 values from all around the program, simply printing them to the debug output will only take a few seconds to add to your program. (If you can't do this easily, then you're not encapsulating your data very well).
Put a breakpoint on the destructor of the class you're interested in, or at the start of the shutdown process just before you destroy the objects, or the last line of code in your program (for statics) (etc) and just use the debugger to drill down into the data.