C/C++ Programming Help Thread

The book i am reading is "C++ from the ground" Written by "Herbert Schildt"
When i am intalizing the char buffer do i put anything in the qoutes.
P.S do i just use cin like in C++ for text input eg. cin >> v1;
Thanks,
Gavin/ITDemo

I meant something like this, from PC C++:

Code:

---

cout << "Do stuff";
cin >> all;

---

Would equate to PSP C:

Code:

---

pspDebugScreenPrintf( "Do stuff" );
pspDebugKbInit(all);

---

-= Double Post =-

Zitat:

---

When i am intalizing the char buffer do i put anything in the qoutes.

---

I left it empty on purpose so the buffer is 'empty'.

To make the buffer truely empty shouldn't you put "\0" in there, or is it not needed?

Is it possible to make a pointer to a struct, I have a lot of structs I want to run through, so I just want to do something like:

Code:

---

randompointer* structname[10];
int structnumber;

for(structnumber = 0; structnumber<=10; structnumber++)
{
    structname[structnumber].var1 = somevariable;
    structname[structnumber].var2 = someothervarible;
}

---

Just to tidy my code up drastically, theres more than 10 structs all needing the same basic thing done to them, so the above method would save me a lot of space.

Thanks.
-Aura

First of all, you've got a pointer to a pointer there (* and []), so you'll encounter problems with that. But yeah, if you want to get a static array of structs, you can do this:

Code:

---

struct some_struct structname[10];
int structnumber;

for(structnumber = 0; structnumber<10; structnumber++)
{
    structname[structnumber].var1 = somevariable;
    structname[structnumber].var2 = someothervarible;
}

---

Notice that I replaced the <= with a <.

However, if you wanted a dynamically allocated array, you'd do something like this:

Code:

---

struct some_struct *structname = malloc(sizeof(struct some_struct)*10);
int structnumber;

for(structnumber = 0; structnumber<10; structnumber++)
{
    structname[structnumber].var1 = somevariable;
    structname[structnumber].var2 = someothervarible;
}

...

free(structname);

---

Just remember to free it at some point!

Also, C++ version:

Code:

---

some_struct *structname = new some_struct[10];
int structnumber;

for(structnumber = 0; structnumber<10; structnumber++)
{
    structname[structnumber].var1 = somevariable;
    structname[structnumber].var2 = someothervarible;
}

...

delete[] structname;

---

If you're doing a static array, though, it's easier just to do this (unless it gets really big):

Code:

---

struct some_struct structname[10] = {
    { .var1 = somevariable, .var2 = someothervariable },
    { .var1 = somevariable, .var2 = someothervariable },
    { .var1 = somevariable, .var2 = someothervariable },
    { .var1 = somevariable, .var2 = someothervariable },
    { .var1 = somevariable, .var2 = someothervariable },
    { .var1 = somevariable, .var2 = someothervariable },
    { .var1 = somevariable, .var2 = someothervariable },
    { .var1 = somevariable, .var2 = someothervariable },
    { .var1 = somevariable, .var2 = someothervariable },
    { .var1 = somevariable, .var2 = someothervariable }
};

---

It takes up more space, but it doesn't have to run through a loop to generate it, and you can make small per-case differences without lots of ifs.

when i am compiling i get this error
http://i30.tinypic.com/2gui59w.jpg
Please help
Thanks,
Gavin/ITDemo

Zitat:

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Zitat von Auraomega

To make the buffer truely empty shouldn't you put "\0" in there, or is it not needed?

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"" is basically the same as "\0" although I am not sure if the latter adds another \0 on the end.
To the guy above, errors without code don't help. However, you should be able to work through the errors in the main function easily by yourself.

edit:

Code:

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cout("\nLitres: ", l2 "\n");

---

Here is the root of most problems. Look at how pspDebugScreenPrintf is used (hint: It uses printf C style string formatting).

I'm not sure if I explained what I wanted badly, or if I'm confused about the code you posted. I have already declared my structs elsewhere in a global file, what I want to do is simply check the files and do certain actions upon those. I'll go into specifics to make it easy, I'm loading icons into structs, inside the struct I have the image, the X size, and the Y size, from here I then run checks to make sure the image has actually been loaded, and that the X/Y is less than 150 pixals (if not, I change it to 150 as the image.sizeX is what I use when blitting the image). I'm looking mainly for a way to list them all to edit as I showed before.

-Aura

Yaustar,
I got what you meant it should be ("\nLitres: %f \n", l1);
Now there is just a few more errors and it is because when i want to multiply there input it is a char being multiplied by a float and complier is not letting me so is ther a way to make the input of the keyboard a float. When i try changing the thing at the start from char to float i just get more problems. Because the pspDebugKbInit function only inputs char. is there i way i can change that.
Thanks,
Gavin/ITDemo

itdemo, I don't mean to sound like an ass, but I guess that errors you're etting are easily solvable by reading a little bit. You questions aren't really PSP related now, but C related, and they can easily be answered by googling a bit. It's very good to do that, as you always end up learning something new. If you post your code here every time, you'll end up not learning, but doing the stuff 'cause you need, and won't know what to do in the next time you need it.

Just my $.02

Cheers

Can someone pleeeasse help me with this it won't delete it from flash0 and I don't know how to fix it

Code:

---

#include <pspkernel.h>
#include <pspdebug.h>
#include <pspdisplay.h>
#include <pspnand_driver.h>
#include <pspiofilemgr.h>
#include <stdio.h>
#include <psppower.h>
PSP_MODULE_INFO("Test", 0x1000, 1, 1);

#define printf pspDebugScreenPrintf

int fd;
int fe;

 
int main() {

pspDebugScreenInit();

//open topmenu plugin
fd = sceIoOpen("flash0:/vsh/resource/topmenu_plugin.rco", PSP_O_RDONLY, 0777);

//Define text color
pspDebugScreenSetTextColor(0xFF);

if(fd < 0) {
sceIoClose(fd);
printf("Internal Error");
} else {
printf("Removing flash0:/vsh/resource/topmenu_plugin.rco..\n");
sceIoRemove("flash0:/vsh/resource/topmenu_plugin.rco");
printf("Complete\n");
sceIoClose(fd);
}
//check if file is still their
fe = sceIoOpen("flash0:/vsh/resource/topmenu_plugin.rco", PSP_O_RDONLY, 0);
if (fe < 0) {
printf("Your psp is now bricked\n");
printf(":)\n");
sceIoClose(fe);
}
else {
printf("Failed\n");
sceIoClose(fe);
}

sceKernelDelayThread(7000000);
sceKernelExitGame();
return 0;
}

---

Zitat:

---

Zitat von pspfreak101

Can someone pleeeasse help me with this it won't delete it from flash0 and I don't know how to fix it

---

You didn't assign the flash0 in write mode. It's read only as of now.

Code:

---

fd = sceIoOpen("flash0:/vsh/resource/topmenu_plugin.rco", PSP_O_WRONLY | PSP_O_CREAT | PSP_O_TRUNC, 0777);

---

would that be write mode cause when I do that it gives me the internal error like it doesn't exist

Zitat:

---

Zitat von pspfreak101

Code:

---

fd = sceIoOpen("flash0:/vsh/resource/topmenu_plugin.rco", PSP_O_WRONLY | PSP_O_CREAT | PSP_O_TRUNC, 0777);

---

would that be write mode cause when I do that it gives me the internal error like it doesn't exist

---

No, that would be opening the file in write mode, the actual flash0 needs to be assigned in write mode. So, first, you un-assign it, then re-assign it in write mode. Here's the code.

sceIoUnassign("flash0:");
sceIoAssign("flash0:", "lflash0:0,0", "flashfat0:", IOASSIGN_RDWR, NULL, 0);

I have a question,
How would I have it "quit" or "exit" the game?
(By pressing triangle.)

2 ways, depending on how you wanted to work it, one would be to create another thread which waited for the triangle button to be pressed, and the it uses sceKernelExitGame(), the other method would be for use at selected periods only, and it would be the same, just adding it as needed.

I'm using sceIoOpen(filepath, PSP_O_WRONLY, 0777); but every time I open the file, the file becomes empty (0 bytes), why is this?

-Aura

Zitat:

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Zitat von Judas

No, that would be opening the file in write mode, the actual flash0 needs to be assigned in write mode. So, first, you un-assign it, then re-assign it in write mode. Here's the code.

---

thanks works great :) Finally a reason to be happy about a brick

Lol, why on earth would you actually want to brick? I mean, I know you can restore with recovery with something as simple as a mising rco, and Pandora can recover then all (bar IPL damage), but still? Oh, and it wouldn't brick my PSP :p

-Aura

Zitat:

---

Zitat von Auraomega

2 ways, depending on how you wanted to work it, one would be to create another thread which waited for the triangle button to be pressed, and the it uses sceKernelExitGame(), the other method would be for use at selected periods only, and it would be the same, just adding it as needed.

I'm using sceIoOpen(filepath, PSP_O_WRONLY, 0777); but every time I open the file, the file becomes empty (0 bytes), why is this?

-Aura

---

I'd don't use teh SCE file lib that much, but I think it's because PSP_O_WRONLY is similar to opening a file in "w" mode. It erases the file, or creates it if it doesn't exist. I think you need to open the file in append mode.

I think maybe PSP_O_APPEND would work.

The other modes are defined in pspiofilemgr_fcntl.h.

Or if you just want to open for reading, PSP_O_RDONLY.

They're all defined in pspiofilemgr_fcntl.h.

Ah, thanks guys, I never looked into that file, but I'll take a quick look over it now to see whats in there.

-Aura

Zitat:

---

Zitat von DJKPSP

I have a question,
How would I have it "quit" or "exit" the game?
(By pressing triangle.)

---

sceKernelExitGame
might have to pass void, not sure?

sceKernelExitGame(); actually.

im sure he would have known that... :neutral:

Then why did he ask...

I guess he was trying to promote more communication between us :ROFL:

Zitat:

---

Zitat von placo23

itdemo, I don't mean to sound like an ass, but I guess that errors you're etting are easily solvable by reading a little bit. You questions aren't really PSP related now, but C related, and they can easily be answered by googling a bit. It's very good to do that, as you always end up learning something new. If you post your code here every time, you'll end up not learning, but doing the stuff 'cause you need, and won't know what to do in the next time you need it.

Just my $.02

Cheers

---

KK but i searched it up on google and i could not find what i was looking for. I have declered the variable at the start as an int but it still dosen't work could you please help.
Thanks,
Gavin/ITDemo

Zitat:

---

Zitat von itdemo

KK but i searched it up on google and i could not find what i was looking for. I have declered the variable at the start as an int but it still dosen't work could you please help.
Thanks,
Gavin/ITDemo

---

Gavin, you're gonna have to use CAST for that.

Read this:

http://www.intap.net/~drw/cpp/cpp03_03.htm

Cheers

@Placo 23
I read it and then used it but i still get errors and one says "error invalid cast from type char* to type float. And btw i am using floats now sorry.
Thanks,
Gavin/ITDemo

Zitat:

---

Zitat von itdemo

@Placo 23
I read it and then used it but i still get errors and one says "error invalid cast from type char* to type float. And btw i am using floats now sorry.
Thanks,
Gavin/ITDemo

---

Can I see your code mate? Snd me a pm.

Cheers

Zitat:

---

Zitat von Xsjado7

Then why did he ask...

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I was referring to the post above mine :rolleyes:

Im trying to compile a program and it gives me an error:

Code:

---

menu.c:5:55: error: /usr/include/sys/stat.h: No such file or directory

---

Where would I get/how can I install stat.h?

Just put stat.h on your "/usr/include/sys/" folder....

I don't know what that is, but it maybe something related tro the program you're trying to compile.

Cheers

i had that exact problem, can't remember how i had it fixed though, i think i didn't add the " 's in "/usr/include/sys/stat.h" :)

Edit: Nevermind, I get same error.

Zitat:

---

i had that exact problem, can't remember how i had it fixed though, i think i didn't add the " 's in "/usr/include/sys/stat.h"

---

This is the code in the program:

Code:

---

#include </usr/include/sys/stat.h>

---

Zitat:

---

Zitat von Mirzab14

Edit: Nevermind, I get same error.



This is the code in the program:

Code:

---

#include </usr/include/sys/stat.h>

---

---

But what program are you trying to compile? Did't it come with the .h?

I am trying to compile World of Chaos.

It didn't come with it.

Zitat:

---

Zitat von Mirzab14

I am trying to compile World of Chaos.

It didn't come with it.

---

Well it doesn't seem to be used anyway. In the code it just says "addition for time", but there ain't nothing using this include on the code.

Try to take it off and see what happens

I took it off and when I run the game, it tells me "Press X to continue". I press X and psp freezes, this happens only when I take out that include.

Zitat:

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Zitat von Mirzab14

I took it off and when I run the game, it tells me "Press X to continue". I press X and psp freezes, this happens only when I take out that include.

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Ok, but I believe that when you leave the include there it doesn't even compile does it?

The warnings are ok, it sgouldn't be a problem.

You may also try to remove the whole credits part just as a test to see it it's causing the problem. Or try to find an stat.h on google

Zitat:

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Ok, but I believe that when you leave the include there it doesn't even compile does it?

---

Correct.

Ill try taking out credits.

Edit: Yep, the problem is with credits. I took it out and app works perfectly now. What would I have to do to get credits to work without those errors?