How to copy a few chars from a char[] to a char* in C?

char buffer[512] = "GET /testfile.htm HTTP/1.0";
char* filename; // I want *filename to hold only "/testfile.htm"

msgLen = recv(connecting_socket, buffer, 512, 0);
strncpy(filename, buffer+5, msgLen-9);

strncpy(filename, buffer+5, msgLen-9);

char filename[512];

char buffer[512] = "GET /testfile.htm HTTP/1.0";
char filename[512]; // I want *filename to hold only "/testfile.htm"

msgLen = recv(connecting_socket, buffer, 512, 0);
strncpy(filename, buffer+4, msgLen-4-9);
//the first parameter should be buffer+4, not 5. Indexes are zero based.
//the second parameter is count, not the end pointer. You should subtract
//the first 4 chars too.

filename[msgLen-4-9] = 0;

memcpy(filename, buffer+4, msgLen-4-9);
fileName[msgLen-4-9] = 0;

char* filename;

char filename[SOME_BUFFER_SIZE];

char filename[512]

filename = (char *)malloc(msgLen - 9  - 6 + 1 ); /* + 1 for the terminating null */

filename = (char*)malloc(512*sizeof(char));