C/C++ Programming Help Thread

[Xsjado7]

Ok, iv got past that error showing when writing files but now the program runs fine but nothing is written at all

    pspDebugScreenInit();
    char file_data[5];
    char contents[5];
    sprintf(file_data, "hello");
    int file = sceIoOpen("ms0:/file.txt", PSP_O_WRONLY, 0777);
    if(file > 0)printf("File Opened\n");
    if(file <= 0)
    {
            printf("Failed Opening File, Exitting");
            sceKernelDelayThread(1000000);
            sceKernelExitGame();
    }
    sceKernelDelayThread(1000000);
    int write = sceIoWrite(file, file_data, 5);
    if(write > 0)printf("Data Written to file\n\n");
    if(write <= 0)
    {
            printf("Failed Writing to File, Exitting");
            sceKernelDelayThread(1000000);
            sceKernelExitGame();
    }
    sceKernelDelayThread(1000000);
    printf("Reading file contents\n");
    sceIoRead(file, contents, 5);
    sceKernelDelayThread(1000000);
    printf("File contents: %s\n\n", contents);
    sceKernelDelayThread(3000000);
    printf("Exitting in:\n");
    sceKernelDelayThread(1000000);
    printf("3...\n");
    sceKernelDelayThread(1000000);
    printf("2...\n");
    sceKernelDelayThread(1000000);
    printf("1...\n\n");
    sceKernelDelayThread(1000000);
    printf("See Ya...\n");
    sceKernelDelayThread(1000000);
    sceKernelExitGame();

Probably another stupid thing iv missed. Any help would be great, thanks

EDIT: Found and fixed problem

[placo23]

HI guys I've got the following C struct:

struct songinfo

  {

  char filename[256];

  char artist[64],song[64];	/* Song info, from ID3 */

  int year;
  } s;

I'm trying to populate it's members using:

s.filename = tune;

OR

strcpy(s->filename,tune);

But I always get "incompatible types in assignment" even if I try like

s.filename = "test";

What could I be doing wrong on that?

Thanks,

[Grimfate126]

HI guys I've got the following C struct:

struct songinfo

  {

  char filename[256];

  char artist[64],song[64];	/* Song info, from ID3 */

  int year;
  } s;

I'm trying to populate it's members using:

s.filename = tune;

OR

strcpy(s->filename,tune);

But I always get "incompatible types in assignment" even if I try like

s.filename = "test";

What could I be doing wrong on that?

Thanks,

try using typedef:

typedef struct
{
    char filename[256];
    char artist[64],song[64];	/* Song info, from ID3 */
    int year;
} SongInfo;

SongInfo s;

etc...

[placo23]

try using typedef:

typedef struct
{
    char filename[256];
    char artist[64],song[64];	/* Song info, from ID3 */
    int year;
} SongInfo;

SongInfo s;

etc...

Right, just did it, but am still getting exactly the same error.

Any other ideas?

[Grimfate126]

Right, just did it, but am still getting exactly the same error.

Any other ideas?

ah, i see why. "test" is a const char, and your array is made of chars, so thats why throwing the incompatible types error. use pointers instead.

[yaustar]

Since you haven't told us what datatype variable tune is, we can't tell you the problem.

This should work however

strncpy( s.filename, "test", 255 );

If it doesn't then post up the actual code. There must be something else in the source that is causing that error.

[Grimfate126]

wouldnt pointers be a better way to handle something dynamic such as this?

[yaustar]

What is dynamic about strings?

[Grimfate126]

dynamic as in he doesnt know the exact length of every song, so (i think) it would be better to make a char pointer instead of allocating a static array.

*gets ready to get pwned*

[_dysfunctional]

Well, filenames have a max length (256 bytes, IIRC) and ID3 tags also have a set amount of space set for song titles, so that is irrelevant.

[Grimfate126]

ah ok, forget my post then.

great, now im getting pwned by 2 people. >.<

[pHysiX]

wat is the difference between signed and unsigned int?

i know that eg:

printf("&d&\n", 455);
printf("%u"\n", 455);

will show 455 then 65081 on the next line. but wat does of of this signed and unsigned mean and how does it work? ta in advance

[Insert_Witty_Name]

http://www.space.unibe.ch/comp_doc/c...ata_types.html

Scroll down to see the range of values that can be stored in each data type.

[placo23]

Since you haven't told us what datatype variable tune is, we can't tell you the problem.

This should work however

strncpy( s.filename, "test", 255 );

If it doesn't then post up the actual code. There must be something else in the source that is causing that error.

I'm sorry for that, but that will be a string, in this case, the file name

[Xsjado7]

Quick question, how do i go about checking the contents of a string? I read that you cant do it by:

if(string == "something")

[yaustar]

Quick question, how do i go about checking the contents of a string? I read that you cant do it by:

if(string == "something")

C++ strings, yes you can as they overload the == operator. C strings, you can't. Read: http://www.cppreference.com/stdstring/index.html
-= Double Post =-

dynamic as in he doesnt know the exact length of every song, so (i think) it would be better to make a char pointer instead of allocating a static array.

*gets ready to get pwned*

Which is one of the reasons why I used strncpy instead of strcpy so he doesn't overrun the buffer.

If you use a char * and dynamically allocate the space for the string, you have to remember to free it and re-allocate it if the string length increases in size. More maintenence work to maintain the string. Static buffers are much easier to handle as they are always on the stack. You just have to be aware of buffer overruns.

The simplest solution is to use C++ strings. Much easier and cleaner.

[Auraomega]

How do I use sceKernelExitVSHVSH properly?

From the header:

struct SceKernelLoadExecVSHParam {
/** Size of the structure in bytes */
    SceSize     size;
/** Size of the arguments string */
    SceSize     args;
/** Pointer to the arguments strings */
    void * argp;
/** The key, usually "game", "updater" or "vsh" */
    const char * key;
/** The size of the vshmain arguments */
    u32 vshmain_args_size;
/** vshmain arguments that will be passed to vshmain after the program has exited */
    void *vshmain_args;
/** "/kd/pspbtcnf_game.txt" or "/kd/pspbtcnf.txt" if not supplied (max. 256 chars) */
    char *configfile;
/** An unknown string (max. 256 chars) probably used in 2nd stage of loadexec */
    u32 unk4;
/** unknown flag default value = 0x10000 */
    u32 unk5;
}; 

int sceKernelExitVSHVSH(struct SceKernelLoadExecVSHParam *param);

I believe that this function should allow me to restart the PSP (so to speak) loading another pspbtcnf.txt (or bin in newer firmwares) file. I have made param.configfile = "/kd/pspbtcnf_alt.bin" but with no success, the VSH just reboots reading from the original pspbtcnf.bin file. Does anyone here have any experiance with this, and/or can anyone see any problems with what I've done?

Thanks.
-Aura

[SuperBatXS]

Hey guys,
This is a quick question, but how do you flip an image using OSLib? I couldn't find it in the documentations or the samples, and i could only find rotations and zoom, etc. I have a character facing right (my signature tells it all), but i want to make him face left using code.

Thanks.

[Xsjado7]

As far as i know, you cant

[Grimfate126]

you can. look carefully. i have used it before, and it works. I dont currently have oslib so i cant look for you, but im 100% sure its there.

[DJKPSP]

I have a question,
How would can I run another .PBP file in the same directory using C/C++?
Such as after EBOOT.PBP does something then it goes onto START.PBP or whatever name it would be.

[Anti-QuickJay]

Search for it, their are tons of example's on running .PBP files.

[eldiablov]

I have a question,
How would can I run another .PBP file in the same directory using C/C++?
Such as after EBOOT.PBP does something then it goes onto START.PBP or whatever name it would be.

You arent really supposed to request code here.

[Judas]

I have a question,
How would can I run another .PBP file in the same directory using C/C++?
Such as after EBOOT.PBP does something then it goes onto START.PBP or whatever name it would be.

It's not that we don't do code requests, it's just that it'll help you be a better developer if you're able to search first. And this is very common, so you obviously didn't search.

[SuperBatXS]

Speaking of searching...er, i still couldn't find a way i can flip an image (my signature into moving left not right). I did find one thing: the oslib samples of Mickey. I found out that you can flip Mickey by deforming him...kind of wierd but once you go past a point it works. However, i was wondering if there is an easier way.

Thanks.

[Xsjado7]

Hey, i just set up a function in my game that reads a config file to get controls. The config file contains something like this:

action=cross
action2=square

and then i have stuff like:

action_control[10];
action2_control[10];

Now i thought i could just read the config file, then use sprintf(); to print say, cross to action and square to action 2 and then go(with OSLib):

 if(osl_keys->pressed.action_control)do whatever;
if(osl_keys->pressed.action2_control)do whatever;

But that didnt work because it expects either cross or square or circle and so on. So how would i go about using the string that contains the control specified by the user to control my game, any help would be great. Thanks(sorry for bad explaination)

Also, thanks Yaustar for that page. I got my problem all sorted out

[SuperBatXS]

Well, how about doing this.

Options.txt file:

c

or

s

Where "c" is cross and "s" is square. Then, read the contents of the file:

/**************************************************
             Before While Loop
***************************************************/
//array for storing characters that will be read by txt file
char xoptions[1];

//Delare file, and open
FILE *options;
if ((options = fopen("./options.txt","rb")) == NULL)
{
     printf("Please Check Your Options.txt");
}

//Store file contents into array
xoptions[fread(xoptions, 1, 1, options)] = 0;

//Close file
fclose(options);


/**************************************************
               While Loop
***************************************************/


//If array is c or s, then do whatever
switch(xoptions[0]) {
    case 'c': if(osl_keys->pressed.cross) do whatever; break; //if cross, then do whatever
    case 's': if(osl_keys->pressed.square) do whatever; break; //if square, then do whatever
    }

At least, that's what i would do. There are a million ways to do it, and there are probably better ways.

[Xsjado7]

yeah, thats the way i was going to do it but i have 12 options and 12 buttons used so i would have to go through every option and do something like:

char cross[10];
sprintf(cross, "cross");
char square[10];
sprintf(square, "square");
char triangle[10];
sprintf(triangle, "triangle");

...and so on to be compared with the string entered by user in config. Then:

if(strncmp(action_button, cross)
{
if(osl_keys->pressed.cross)do option1;
}
if(strncmp(action_button, square)
{
if(osl_keys->pressed.square)do option1;
}
if(strncmp(action_button, triangle)
{
if(osl_keys->pressed.triangle)do option1;
}

and so on for every option using every button
If worse comes to worse il do it like that but i would prefer doing it another way

[SuperBatXS]

I'm still confused with your question. If you want to add more buttons, then put more "case"s. If you want to add more options, then make the array longer and read more characters. Also, if you have a bunch of "else if"s, then simply use switch and put your cases. It seems easier to me, especially when making menus.

[_dysfunctional]

How about searching information on C structs before asking retarded questions.