I have a directory in which there is only one file with a big name string. The matlab m-file which fopens this file is in some other directory. How can I fopen this only file without explicitly writing down its name in the m-file? The reason that writing down the filename is not desirable is because there are atleast nine hundred such directories with a single file in each of them, and every filename is different. Each directory is properly numbered though - dir001, dir 002, ..., dir934. Each of these contain exactly one file. And the filetype is also the same.