h6. [[Internet]] h6(. » [[Internet SWI Calls|SWI Calls]] h6((. » Socket_Ioctl h2. Socket_Getsockopt h5. (SWI &41212) |_<^{width:4em}. Entry | | |<^. R0 |<^. Socket descriptor | |<^. R1 |<^. Operation to perform | |<^. R2 |<^. Pointer to buffer containing the value (writes) or to return the value into (reads) | |_<^{width:4em}. Exit | | |<^. R0 |<^. Corrupted | h4. Use The purpose of this call is to perform miscellaneous I/O control operations on a socket. h4. Berkeley sockets equivalence This SWI directly corresponds to the function "ioctl":https://pubs.opengroup.org/onlinepubs/9699919799/functions/ioctl.html and would ordinarily be called from C using the <code>socketioctl()</code> function in <code>socklib.h</code>. h4. Notes The different function name is needed because in RISC OS file descriptors and socket descriptors come from two different number spaces, while under Unix they share the same number space so a single <code>ioctl()</code> function serves to manipulate either type. h4. See also * [[Internet]] * [[Socket_Creat]]