Here is a list of all documented struct and union fields with links to the struct/union documentation for each field:

- o -

object : lwm2m_obj_ipso_sensor_base
object_id : lwm2m_obj_ipso_sensor_base
observer : gcoap_observe_memo_t
occupied : suit_storage_ram_region_t , usbus_cdcacm_device , usbus_hid_device
ocp : gnrc_rpl_of_t , gnrc_rpl_opt_dodag_conf_t
OCR : mega_timer_t
OD : msp430_port_p7_p8_t , msp430_port_t
odr : l3gxxxx_params_t
ODR : LIS2DH12_CTRL_REG1_t
odr : lis3dh_params_t , lis3mdl_params_t , qmc5883l_params_t
oe_pin : pca9685_params_t
OEIM : cc2538_uart_t
OEMIS : cc2538_uart_t
off : ieee802154_radio_ops
off_ctl : tcp_hdr_t
offloadACKTimer() : dsme::DSMEPlatform
offloadCCAEvent() : dsme::DSMEPlatform
offloadRXDoneEvent() : dsme::DSMEPlatform
offloadTimerEvent() : dsme::DSMEPlatform
offloadTXDoneEvent() : dsme::DSMEPlatform
offset : adxl345_params_t , coap_block1_t , coap_optpos_t , evtimer_event , gnrc_ipv6_ext_frag_send_t , gnrc_sixlowpan_frag_fb_t , mag3110_params_t , mma8x5x_params_t , mtd_flashpage_t , nanocoap_fs_dir_t , nanocoap_fs_file_t , riotboot_flashwrite_t , sixlowpan_frag_n_t , sixlowpan_sfr_rfrag_t , suit_param_ref_t , vcdiff_mtd_t , xtimer , ztimer_base
offset_diff : gnrc_sixlowpan_frag_rb_t
offset_flags : ipv6_ext_frag_t
offset_x : lcd_params_t
offset_y : lcd_params_t
OID : cid_t , sdmmc_cid_mmc_t , sdmmc_cid_sd_t
old_sample : entropy_source_tests_prop_t , entropy_source_tests_rep_t
op_mode : hmc5883l_params_t , hmc5883l_t , lis3mdl_params_t
opcode : msc_cbw_rw10_pkt_t , mtd_spi_nor_params_t
open : stdio_provider_t , vfs_file_ops
open_files : vfs_mount_struct
opendir : vfs_dir_ops
operator bool() : riot::unique_lock< Mutex >
operator!=() : riot::thread_id
operator()() : riot::thread_data_deleter
operator+=() : riot::time_point
operator<() : riot::thread_id
operator<< : riot::thread_id
operator<=() : riot::thread_id
operator=() : dsme::DSMEPlatform , riot::thread , riot::unique_lock< Mutex >
operator==() : riot::thread_id
operator>() : riot::thread_id
operator>=() : riot::thread_id
OPMODEACK : aux_sysif_regs_t
OPMODEREQ : aux_sysif_regs_t
ops : gnrc_netif_t , ztimer_clock
opt : can_opt_t , coap_block_slicer_t , ds3231_params_t , gnrc_netapi_opt_t , isotp
opt_codes : dhcpv6_opt_oro_t
opt_num : coap_optpos_t
option : ieee802154_mr_ofdm_conf_t
options : cc2420_t , coap_pkt_t , ctap_config_t , ctap_get_assertion_req_t , ctap_info_t , ctap_make_credential_req_t , xbee_t
options_len : coap_pkt_t
opts : dhcpv6_opt_ia_na_t , dhcpv6_opt_ia_pd_t , dhcpv6_opt_iaaddr_t , dhcpv6_opt_iapfx_t , dose_t
origin : ntp_packet_t
os_mult : lm75_properties
os_res : lm75_properties
os_shift : lm75_properties
OSC : cc2538_sys_ctrl_t
OSC32K : cc2538_sys_ctrl_t
OSC32K_CADIS : cc2538_sys_ctrl_t
OSC32K_CALDIS : cc2538_sys_ctrl_t
OSC_CONF : fcfg_regs_t
OSC_PD : cc2538_sys_ctrl_t
OSCCFG : aon_pmctl_regs_t , aon_wuc_regs_t
OSCICR : prcm_regs_t
OSCIMSC : prcm_regs_t
OSCRIS : prcm_regs_t
osr : qmc5883l_params_t
otaa : gnrc_netif_lorawan_t
otg : bq2429x_fault_t
otg_pin : bq2429x_params_t
out : pcf857x_t , stm32_usbdev_fs_t , usbdev_mock , usbus_control_handler_t
out_buf : usbus_cdcacm_device , usbus_control_handler_t , usbus_hid_device , usbus_msc_device
out_drv : pca9685_params_t
out_lock : usbus_cdcecm_device
out_mode : ds18_params_t
out_mutex : ethos_t
out_ne : pca9685_params_t
out_netif : gnrc_sixlowpan_frag_vrb_t
OUT_OF_RANGE : sdmmc_card_status_t
out_tag : gnrc_sixlowpan_frag_vrb_t
out_urb : usbus_cdcecm_device
output_disable : gpio_pad_ctrl_t
output_enable_override : gpio_io_ctrl_t
output_override : gpio_io_ctrl_t
OVER : cc2538_ioc_t
OVERRUN : sdmmc_card_status_t
oversampling : bmp180_params_t
OVRN_FIFO : LIS2DH12_FIFO_SRC_REG_t
own_addr_type : nimble_autoadv_cfg_t , nimble_netif_accept_cfg_t , nimble_netif_connect_cfg_t
owner : mutex_t , rmutex_t
owner_calling_pc : mutex_t
owner_original_priority : mutex_t
owns_lock() : riot::unique_lock< Mutex >