expected primary-expression & obtaining substrings

hopefully can show me 'best way' substrings.... plans return pointer new string assign currenttext to....

but real problem getting pesky "error: expected primary-expression before 'char'" , pointing @ 'char substr(' on bottom.....

here's code....

code: [select]


#include <mlcd.h>

char scrolltext[255] = "\0";
char currenttext[255] = "\0";
char tmpstr[255] = "\0";
int curpos = 0;
int curdir = 1;
mlcd mlcd(19200);

char substr(*char, int, int);

void setup()
{
 mlcd.start();
 mlcd.clrscrn();
 strcat(scrolltext, "bluegrass digital inc.");
}

void loop()
{
 while (1)
 {
   if (curdir == 1)
   {
     strncat(currenttext, &scrolltext[curpos], 1);
   }
   if (strlen(currenttext) > 16)
   {
     //strncpy(currenttext, *(&currenttext+1), 16);
   }
   if (curpos < strlen(scrolltext)) {curpos += curdir;} else {curdir = -1;}
   mlcd.setcursor(16 - strlen(currenttext), 1);
   mlcd.sendtext(currenttext);
   delay(200);
 }
}

char substr(*char srcstr, int start, int length)
{
}


not sure 'best way' assuming want substr create new string, done follows (note * follows char):

code: [select]

char*  substr(char* srcstr, int start, int length)
{
// need allocate memory new string, can using malloc:
 char* newstring = (char*)malloc(length+1);
 if(newstring) {  // check malloc able allocate memory
     strncpy(newstring,&srcstr[start], length); // copy source string
     newstring[length] = '\0';  // make sure there terminating 0    
 }
 return newstring;  
}

don't forget should free string when done if want reuse memory

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