C/C++ Programming Help Thread

[hallo007]

unsigned char 0 - 255

signed char -127 to 127

when you just say char , it will be signed

[Auraomega]

did you put this in all the files?

#include "global.h"

Yup, I sorta solved that problem last night (wasn't because I'd left the #include "global.h").

Now though, when I type global.variable, it says its unrecognised.

-Aura

[hallo007]

typedef struct
{
     int data[50];
     }DATEBUFFER;      
//some code
DATABUFFER someInfo = { 0x00 , 0x00 , 0xFF , 0xFF , 0xFF , 0xFF , 0xB4 , 0x25 , 0x00 , 0x00 , 0xFF , 0xFF , 0xFF , 0xFF , 0xFF , 0XFF , 0xFF , 0xFF , 0xCC , 0x00 , 0x00 , 0x00 , 0xFF , 0xFF , 0xFF , 0xFF , 0xFF , 0xFF , 0xFF , 0xFF , 0x3C , 0x83 , 0x00 , 0x00 , 0xFF , 0xFF };

warning: accordances are lacking around beginning value
warning: (near initialization for ‘someInfo.data’)

[JaSo PsP]

You've only initialized 36 variables? I'm not sure what the actual problem is though...

[hallo007]

I dont understand the two warnings , that's the problem

[Archaemic]

unsigned char 0 - 255

signed char -127 to 127

when you just say char , it will be signed

signed char is -128 to 127.

typedef struct
{
     int data[50];
     }DATEBUFFER;      
//some code
DATABUFFER someInfo = { 0x00 , 0x00 , 0xFF , 0xFF , 0xFF , 0xFF , 0xB4 , 0x25 , 0x00 , 0x00 , 0xFF , 0xFF , 0xFF , 0xFF , 0xFF , 0XFF , 0xFF , 0xFF , 0xCC , 0x00 , 0x00 , 0x00 , 0xFF , 0xFF , 0xFF , 0xFF , 0xFF , 0xFF , 0xFF , 0xFF , 0x3C , 0x83 , 0x00 , 0x00 , 0xFF , 0xFF };

warning: accordances are lacking around beginning value
warning: (near initialization for ‘someInfo.data’)

typedef struct
{
     int data[50];
} DATABUFFER;      
//some code
DATABUFFER someInfo = { { 0x00 , 0x00 , 0xFF , 0xFF , 0xFF , 0xFF , 0xB4 , 0x25 , 0x00 , 0x00 , 0xFF , 0xFF , 0xFF , 0xFF , 0xFF , 0XFF , 0xFF , 0xFF , 0xCC , 0x00 , 0x00 , 0x00 , 0xFF , 0xFF , 0xFF , 0xFF , 0xFF , 0xFF , 0xFF , 0xFF , 0x3C , 0x83 , 0x00 , 0x00 , 0xFF , 0xFF } };

Note the changes.
Also, I don't know if this will work because it doesn't initialize the whole array.

[Mr305]

pointer targets differ in signedness;

What does that mean?

[JaSo PsP]

pointer targets differ in signedness;

What does that mean?

Im guessing its something todo with UNSIGNED and SIGNED variables... The two targets aren't the same 'signedness'.

[psp_jono]

"pointer targets differ in signedness" generally means you are trying to point a unsigned char pointer at signed char data or vice versa.

Heres an example that would generate this warning/error message:

char variable;
unsigned char* variable_ptr = &variable;

It could be more complicated but it will boil down to something like this happening. I'm pretty sure the above code wouldn't compile.

To avoid it you could use a type cast, but it could be bad because 'variable' might contain value -121 but if you access it through 'variable_ptr' it will give you value 135.

Example:

	char v = -121;
	unsigned char* v_ptr = (unsigned char*)&v;
	
	printf( "%d", *v_ptr);

The above code would print '135' even though you set the value to -121.

Hope that helps.

Also, I don't know if this will work because it doesn't initialize the whole array.

If an initialiser list is smaller than the array, the rest of the array is filled with 0 so it shouldn't be a problem.

[pspballer07]

Yup, I sorta solved that problem last night (wasn't because I'd left the #include "global.h").

Now though, when I type global.variable, it says its unrecognised.

-Aura

are you serously typing "global.variable" or "global.(insert var here)"

[psp_jono]

We might need to see some code to sort out the problem, but if I had to guess I would say that you haven't actually declared a variable called global.

Underneath were you define the global struct you need to declare a variable of that type.

ie.

typedef struct
{
   int a, b, c, d;
} Global;

extern Global global;   //  <- This bit

Just a guess :), if not show a little code and someone will figure it out.

[eldiablov]

apologies, wrong thread

[Auraomega]

are you serously typing "global.variable" or "global.(insert var here)"

Hi, nah even I'm not that stupid (I think...), I noticed that the code you sent me was causing an error, so I slightly modified it, solved it not long after making that post... I'm just getting into the habit of not editing posts lately.

I'm STILL stuck on using GU in the XMB, its driving my nuts now, I've made a post on ps2dev, and no-one has replied. Has anyone got any idea how I can do something even as simple as one of the samples in the XMB without it crashing?

-Aura

[_dysfunctional]

Hi, nah even I'm not that stupid (I think...), I noticed that the code you sent me was causing an error, so I slightly modified it, solved it not long after making that post... I'm just getting into the habit of not editing posts lately.

I'm STILL stuck on using GU in the XMB, its driving my nuts now, I've made a post on ps2dev, and no-one has replied. Has anyone got any idea how I can do something even as simple as one of the samples in the XMB without it crashing?

-Aura

:o Yes.

[Auraomega]

:o Yes.

Argh, maybe some source code or something would be handy... I've tried looking at the DSX code, and either I'm missing some code, or I'm stupid, because I really can't see how it works, at all.

-Aura

[_dysfunctional]

Well, you post some code and we will see if we can work out your problems.

For future reference, coming to #psp-programming IRC channel will get you much faster results than posting here. It is on irc.freenode.net. I would suggest the clients, Xchat, Konversation, *****X, or mIRC.

[Auraomega]

Well, you post some code and we will see if we can work out your problems.

For future reference, coming to #psp-programming IRC channel will get you much faster results than posting here. It is on irc.freenode.net. I would suggest the clients, Xchat, Konversation, *****X, or mIRC.

The code I'm using currently is the exact same peice in the samples (logic), I just changed little bits. I'm using that code because I know its made by someone who knows what their doing, once I get that working I'll change the bits I can to do what I want.

As for the IRC channel, I might give that a shot, cheers.

-Aura

[pspballer07]

Hi, nah even I'm not that stupid (I think...), I noticed that the code you sent me was causing an error, so I slightly modified it, solved it not long after making that post... I'm just getting into the habit of not editing posts lately.

haha k.
What did u fix? (so I know for the future)

[Auraomega]

haha k.
What did u fix? (so I know for the future)

This is the code you said

typedef struct Global
{
      //put all global vars here
     float Varf;
};

extern Global global;

I simply changed it to...

typedef struct
{
     float Varf;
}Global;

I noticed that this was how it was done by taking a look at a couple of the files in the include folder

-Aura

[psp_jono]

Are you sure that was the problem?

typedef struct Global
{
    // whatever variables
};

and

typedef struct
{
    // whatever variables
} Global;

are both perfectly legal and should give the same result.

And to be able to access the member variables of a structure there must be an instance of it, which is why you will need to declare a global variable of type 'Global'.

If you want several files to all be able to access the same global variables, you will need to add this line of code after the structure definition.

extern Global global;

Otherwise there will be no common instance of the global across all the files.

[pspballer07]

@auraomega: that shouldn't make a difference. it works the same way

@psp_jono: I did tell him that "extern Global global;" needs to be in there. He has it in but didn't put that part.

[psp_jono]

@psp_jono: I did tell him that "extern Global global;" needs to be in there. He has it in but didn't put that part.

Yeah, that post wasn't actually meant for you, I was telling Auraomega because I thought he had removed it.

[_dysfunctional]

Are you sure that was the problem?

typedef struct Global
{
    // whatever variables
};

and

typedef struct
{
    // whatever variables
} Global;

are both perfectly legal and should give the same result.

And to be able to access the member variables of a structure there must be an instance of it, which is why you will need to declare a global variable of type 'Global'.

If you want several files to all be able to access the same global variables, you will need to add this line of code after the structure definition.

extern Global global;

Otherwise there will be no common instance of the global across all the files.

:o

I wouldn't be to sure, mate.

#include <stdio.h>

typedef struct ThisWontWork
{
        int myVar;
        int myOtherVar;
};

int main(int argc, char* argv[])
{
        ThisWontWork myStruct;
        myStruct.myVar = 1;
        myStruct.myOtherVar = 1;

        return 0;
}

Gives me:

[email protected]:~/.temp/jono_struct$ gcc main.c -o typedef_struct
main.c:7: warning: useless storage class specifier in empty declaration
main.c: In function ‘main’:
main.c:11: error: ‘ThisWontWork’ undeclared (first use in this function)
main.c:11: error: (Each undeclared identifier is reported only once
main.c:11: error: for each function it appears in.)
main.c:11: error: expected ‘;’ before ‘myStruct’
main.c:12: error: ‘myStruct’ undeclared (first use in this function)

BUT, this compiles and runs fine.

#include <stdio.h>

typedef struct ThisWontWork
{
        int myVar;
        int myOtherVar;
} ThisWontWork;

int main(int argc, char* argv[])
{
        ThisWontWork myStruct;
        myStruct.myVar = 1;
        myStruct.myOtherVar = 1;

        return 0;
}

[psp_jono]

Strange, I jut tested it on a small gcc compiler on my pc and it compiled and ran without a problem.

Here is the code, like I said it compiles and runs fine.

#include "stdio.h"

typedef struct
{
	int a;
} Example1;

typedef struct Example2
{
	int a;
};

Example1 global1;
Example2 global2;

int main()
{	
	global1.a = 1;
	global2.a = 2;
	
	printf( "Global:  %d\nGlobal2: %d", global1.a, global2.a);
	
	return 0;
}

I guess it must be a difference in the standards used by the pc compiler I'm using and the psp-gcc compiler.

Thanks, always handy to find these things out.

I should've tested on the psp first :)

[_dysfunctional]

Hm, I compiled the above example in my post with GCC 4.1.2 Ubuntu Linux. Now, I just tried to compile the same example for the psp, and I get:

[email protected]:~/.temp/jono_struct$ make
psp-gcc -I. -I/usr/local/pspdev/psp/sdk/include -G0 -Wall -D_PSP_FW_VERSION=150 -c -o main.o main.c
main.c:10: warning: useless storage class specifier in empty declaration
main.c: In function ‘main’:
main.c:14: error: ‘ThisWontWork’ undeclared (first use in this function)
main.c:14: error: (Each undeclared identifier is reported only once
main.c:14: error: for each function it appears in.)
main.c:14: error: expected ‘;’ before ‘myStruct’
main.c:15: error: ‘myStruct’ undeclared (first use in this function)
make: *** [main.o] Error 1

[email protected]:~/.temp/jono_struct$ psp-gcc --version
psp-gcc (GCC) 4.1.0 (PSPDEV 20060507)

Hm, I'm interested to know which version of GCC you tried compiling with
-= Double Post =-
Ahah! It looks like it is only valid in C++. :P

[psp_jono]

Hmm, I guess it must just be the standard that the compilers adheres to, some standards must be a bit more relaxed.

typedef struct
{
    // member vars
} Structure;

I use the above basically all the time. It must be the most acceptable to the different standards because I've never had a problem with it.

The only exception is if I have a self-referential structure, in which case I just typedef the struct name later.

ie.

struct example
{
    struct example* a;
};

typedef struct example Example;

EDIT: Ahh. I jut saw your footnote and yep you are correct, I'm using a c++ compiler. I didn't even realise :).

Its a small program called jens file editor, it came with a built in gcc compiler.

[_dysfunctional]

Well, you could do:

typedef struct _myStruct
{
     _myStruct* s;
} myStruct;

I believe that would work.

[brethren]

struct tagnameforcompiler {
int variable1;
int variable2;
char variable3;} declarestructvariable1, declarestructvariable2;

declarestructvariable1.va riable1 = 10;
declarestructvariable2.va riable3 = 'C';

[psp_jono]

Well, you could do:

typedef struct _myStruct
{
     _myStruct* s;
} myStruct;

I believe that would work.

I've never seen a self-referential structure defined like that, much better than seperating the typdef from the structure definition. Thanks :)

[vodkkaa]

what is the function to erase the entire nand. no i am not making a bricker (pointless becasue of pandoras battery) my brother cracked his lcd screen and the whole right side doesnt work. Instead of buying a new psp he is waiting for the psp slim. so i just want to try the pandora battery method myself by bricking his psp then recovering it. I also want to see if the psp can recover from a 100% corrupt or missing flash. if you feel its not a good idea to post the function on the forum, please pm me it