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copied!<p>The answer is that you can't, unless your filesystem has a bug. Here's why:</p> <p>There is a system call for renaming your file defined in <code>fs/namei.c</code> called <code>renameat</code>:</p> <pre><code>SYSCALL_DEFINE4(renameat, int, olddfd, const char __user *, oldname, int, newdfd, const char __user *, newname) </code></pre> <p>When the system call gets invoked, it does a path lookup (<code>do_path_lookup</code>) on the name. Keep tracing this, and we get to <code>link_path_walk</code> which has this:</p> <pre><code>static int link_path_walk(const char *name, struct nameidata *nd) { struct path next; int err; unsigned int lookup_flags = nd->flags; while (*name=='/') name++; if (!*name) return 0; ... </code></pre> <p>This code applies to any file system. What's this mean? It means that if you try to pass a parameter with an actual <code>'/'</code> character as the name of the file using traditional means, it will not do what you want. There is no way to escape the character. If a filesystem "supports" this, it's because they either:</p> <ul> <li>Use a unicode character or something that <em>looks</em> like a slash but isn't.</li> <li>They have a bug.</li> </ul> <p>Furthermore, if you <em>did</em> go in and edit the bytes to add a slash character into a file name, bad things would happen. That's because you could never refer to this file by name :( since anytime you did, Linux would assume you were referring to a nonexistent directory. Using the 'rm *' technique would not work either, since bash simply expands that to the filename. Even <code>rm -rf</code> wouldn't work, since a simple strace reveals how things go on under the hood (shortened):</p> <pre><code>$ ls testdir myfile2 out $ strace -vf rm -rf testdir ... unlinkat(3, "myfile2", 0) = 0 unlinkat(3, "out", 0) = 0 fcntl(3, F_GETFD) = 0x1 (flags FD_CLOEXEC) close(3) = 0 unlinkat(AT_FDCWD, "testdir", AT_REMOVEDIR) = 0 ... </code></pre> <p>Notice that these calls to <code>unlinkat</code> would fail because they need to refer to the files by name.</p>

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