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Concat string (not ended ...)

hi

i tried to concat some string (not ended, can use strcpy, strcat...)

Code:

void analyzeFilename(char *filename, int size, char *led_line)

{

    char CMD_INIT[]={'\0', '\0', '\0', '\0', '\0', '\1', 'Z', '0', '0', '\2'};

    char CMD_TEXT_FILE_TYPE[]={'A'};

    char CMD_FILE_LABEL=filename[0]; //get the first character of filename

    char CMD_HOLD[]={'\142'};

    char CMD_TXT_GREEN[]={'\34','\62'};

    char CMD_END[]={'\04'};

    

    char ALL[sizeof(CMD_INIT) + sizeof(CMD_TEXT_FILE_TYPE) + sizeof(CMD_FILE_LABEL) + sizeof(CMD_HOLD) + sizeof(CMD_TXT_GREEN) + size + sizeof(CMD_END)];

    

    char *p=ALL;

    

    memcpy(p,CMD_INIT, sizeof(CMD_INIT));

    p += sizeof(CMD_INIT); 

    memcpy (p, CMD_TEXT_FILE_TYPE, sizeof(CMD_TEXT_FILE_TYPE)); 

    p += sizeof(CMD_TEXT_FILE_TYPE); 

    memcpy (p, &CMD_FILE_LABEL, sizeof(CMD_FILE_LABEL));

    p += sizeof(CMD_FILE_LABEL); 

    memcpy (p, CMD_HOLD, sizeof(CMD_HOLD)); 

    p += sizeof(CMD_HOLD); 

    memcpy (p, CMD_TXT_GREEN, sizeof(CMD_TXT_GREEN)); 

    p += sizeof(CMD_TXT_GREEN); 

    memcpy (p, filename, sizeof(size)); 

    p += sizeof(size); 

    memcpy (p, CMD_END, sizeof(CMD_END));

    p += sizeof(CMD_END);

    

    printf("msg complet: %s", p);



...

...

}

ok no error at compile time...

but when i display p, i get bullshit...

Code:

printf("msg complet: %s\n", p);

return me

Code:

msg complet: ÿôÿóècÿôÈ

any idea?

You should check to see where p is pointing after all those memcpy()'s. It's pointing to memory right after the string. Maybe you should be printing ALL instead? Also, CMD_END isn't nul-terminated so you shouldn't be trying to print it anyway. Besides, CMD_INIT starts with a '\0' so it will end up printing nothing since it thinks ALL is an empty string.

itsme is correct in that you should be printing from ALL, not p. The issue is that the code is increasing the memory location of p each time it executes:

Code:

p += sizeof(???);

p now no longer points to ALL, but ALL + sizeof(???);

I don't know if that's what you meant to do.