c - Read bytes (chars) from buffer -

i'm working on steganography program in java. got advice able resolve task better in c program. try it, i'm pretty bad in c programing. read 1 gif file , find byte used image separator (0x2c gif format).

i tried write program:

int main(int argc, char *argv[]) {     file *fileptr;     char *buffer;     long filelen = 0;      fileptr = fopen("d:/test.gif", "rb");  // open file in binary mode     fseek(fileptr, 0, seek_end);          // jump end of file     filelen = ftell(fileptr);             // current byte offset in file     rewind(fileptr);                      // jump beginning of file      buffer = (char *)malloc((filelen+1)*sizeof(char)); // enough memory file + \0     fread(buffer, filelen, 1, fileptr); // read in entire file     fclose(fileptr); // close file      int = 0;     for(i = 0; buffer[ ]; i++)     {         if(buffer[i] == 0x2c)         {             printf("next image");         }     }       return 0; } 

could give me advice how repair loop?

could give me advice how repair loop?

option 1: don't depend on terminating null character.

for(i = 0; < filelen; i++) {     if(buffer[i] == 0x2c)     {         printf("next image");     } } 

option 2: add terminating null character before relying on it. potentially unreliable since reading binary file have embedded null characters in it.

buffer[filelen] = '\0'; for(i = 0; buffer[ ]; i++) {     if(buffer[i] == 0x2c)     {         printf("next image");     } }