C file handling program to capitalize the first letter of every word in a file

\* C file handling program to capitalize the first letter of every word in a file *\

# include < stdio.h >
# include < stdlib.h >
# include < string.h >
void   writeData( char* str )
{

FILE* fp ;
//Write data into a file.
fp = fopen("FirstLetter.txt", "w") ;
if (fp == NULL)
      return;

fwrite(str, 1, strlen(str), fp) ;
fclose(fp);

}

void   readData( char* str )
{

FILE* fp ;
char ch = 0 ;
int cnt = 0 ;
fp = fopen("FirstLetter.txt", "r") ;
if (fp == NULL)
      return ;
ch = fgetc(fp) ;
while (ch != EOF)
{
      str[cnt++] = ch ;
      ch = fgetc(fp) ;
}
str[cnt] = 0 ;
fclose(fp) ;

}

int   main( )
{

char wrtStr[50] ;
char readStr[50] ;
int flg = 1 ;
int cnt = 0 ;
printf("\n Enter the test into file : ") ;
gets(wrtStr) ;
writeData(wrtStr) ;
readData(readStr) ;
while (readStr[cnt] != 0)
{
      if (flg == 1 && readStr[cnt] != 0x20)
      {
            readStr[cnt] = readStr[cnt] - 32 ;
            flg = 0 ;
      }
      if (readStr[cnt] == 0x20 && flg == 0)
            flg = 1 ;
      cnt++;
}
writeData(readStr) ;

memset(readStr, 0x00, sizeof(readStr)) ;
readData(readStr) ;
printf(" Original data from file: %s\n", wrtStr) ;
printf(" Update data from file: %s\n", readStr) ;
return 0 ;

}