Source code is
strncpy(fullPath, m_lclDir, TSK_CD_BUFSIZE);
strncat(fullPath, a_dir, TSK_CD_BUFSIZE-strlen(fullPath));
Maybe better code might be
strncpy(fullPath, m_lclDir, TSK_CD_BUFSIZE);
fullPath[TSK_CD_BUFSIZE - 1] = '\0';
strncat(fullPath, a_dir, TSK_CD_BUFSIZE-strlen(fullPath));