1IOCTL(2) 386BSD Programmer's Manual IOCTL(2) 2 3NNAAMMEE 4 iiooccttll - control device 5 6SSYYNNOOPPSSIISS 7 ##iinncclluuddee <<ssyyss//iiooccttll..hh>> 8 9 _i_n_t 10 iiooccttll(_i_n_t _d, _u_n_s_i_g_n_e_d _l_o_n_g _r_e_q_u_e_s_t, _c_h_a_r *_a_r_g_p) 11 12DDEESSCCRRIIPPTTIIOONN 13 The iiooccttll() function manipulates the underlying device parameters of 14 special files. In particular, many operating characteristics of 15 character special files (e.g. terminals) may be controlled with iiooccttll() 16 requests. The argument _d must be an open file descriptor. 17 18 An ioctl _r_e_q_u_e_s_t has encoded in it whether the argument is an ``in'' 19 parameter or ``out'' parameter, and the size of the argument _a_r_g_p in 20 bytes. Macros and defines used in specifying an ioctl _r_e_q_u_e_s_t are 21 located in the file <_s_y_s/_i_o_c_t_l._h>. 22 23RREETTUURRNN VVAALLUUEESS 24 If an error has occurred, a value of -1 is returned and _e_r_r_n_o is set to 25 indicate the error. 26 27EERRRROORRSS 28 IIooccttll() will fail: 29 30 [EBADF] _d is not a valid descriptor. 31 32 [ENOTTY] _d is not associated with a character special device. 33 34 [ENOTTY] The specified request does not apply to the kind of object that 35 the descriptor _d references. 36 37 [EINVAL] _R_e_q_u_e_s_t or _a_r_g_p is not valid. 38 39SSEEEE AALLSSOO 40 execve(2), fcntl(2), mt(4), tty(4), intro(4) 41 42HHIISSTTOORRYY 43 An iiooccttll function call appeared in Version 7 AT&T UNIX. 44 454th Berkeley Distribution March 10, 1991 1 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67