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RL-ARM User's Guide

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RL-ARM User's Guide

RL-RTX
RL-FlashFS
RL-TCPnet
RL-CAN
Example Programs
Library Reference
Data Types
BIT
BOOL
CAN_ERROR
CAN_msg
FILE
S8
S16
S32
S64
U8
U16
U32
U64
Include Files
can_cfg.h
can_error.h
file_config.h
net_config.h
rtl.h
rtx_can.h
rtx_config.h
stdio.h
Reference
_alloc_box
_calloc_box
_declare_box
_declare_box8
_free_box
_init_box
_init_box8
arp_cache_ip
CAN_init
CAN_receive
CAN_request
CAN_rx_object
CAN_send
CAN_set
CAN_start
CAN_tx_object
cgi_func
cgi_process_data
cgi_process_var
com_getchar
com_putchar
com_tx_active
dhcp_disable
fanalyse
fcheck
fclose
fdefrag
fdelete
feof
ferror
ffind
fflush
fformat
ffree
fgetc
fgets
finit
fopen
fprintf
fputc
fputs
fread
frename
fs_EraseSector
fs_get_date
fs_get_time
fs_Init
fs_ProgramPage
fs_spi_EraseSector
fs_spi_Init
fs_spi_ProgramPage
fs_spi_ReadData
fscanf
fseek
ftell
fwrite
get_host_by_name
http_get_info
http_get_lang
http_get_session
http_get_var
igmp_join
igmp_leave
init_ethernet
init_modem
init_serial
init_TcpNet
int_disable_eth
int_enable_eth
interrupt_ethernet
isr_evt_set
isr_mbx_check
isr_mbx_receive
isr_mbx_send
isr_sem_send
main_TcpNet
mci_init
mci_read_config
mci_read_sect
mci_write_sect
modem_dial
modem_hangup
modem_listen
modem_online
modem_process
modem_run
os_dly_wait
os_evt_clr
os_evt_get
os_evt_set
os_evt_wait_and
os_evt_wait_or
os_itv_set
os_itv_wait
os_mbx_check
os_mbx_declare
os_mbx_init
os_mbx_send
os_mbx_wait
os_mut_init
os_mut_release
os_mut_wait
os_sem_init
os_sem_send
os_sem_wait
os_sys_init
os_sys_init_prio
os_sys_init_user
os_tmr_call
os_tmr_create
os_tmr_kill
os_tsk_create
os_tsk_create_ex
os_tsk_create_user
os_tsk_create_user_ex
os_tsk_delete
os_tsk_delete_self
os_tsk_pass
os_tsk_prio
os_tsk_prio_self
os_tsk_self
poll_ethernet
ppp_close
ppp_connect
ppp_is_up
ppp_listen
rewind
send_frame
slip_close
slip_connect
slip_is_up
slip_listen
smtp_cbfunc
smtp_connect
spi_hi_speed
spi_init
spi_send
spi_ss
tcp_abort
tcp_check_send
tcp_close
tcp_connect
tcp_get_buf
tcp_get_socket
tcp_get_state
tcp_listen
tcp_max_dsize
tcp_release_socket
tcp_reset_window
tcp_send
tftp_fclose
tftp_fopen
tftp_fread
tftp_fwrite
timer_tick
tnet_cbfunc
tnet_ccmp
tnet_get_info
tnet_msg_poll
tnet_process_cmd
tnet_set_delay
tsk_lock
tsk_unlock
udp_close
udp_get_buf
udp_get_socket
udp_mcast_ttl
udp_open
udp_release_socket
udp_send
ungetc
Library Files
Appendix

_free_box

Summary 
#include <rtl.h>

int _free_box (
    void* box_mem,    /* Start address of the memory pool */
    void* box );      /* Pointer to the block to free */
Description 

The _free_box function returns a memory block, which was allocated using _alloc_box or _calloc_box, back to the memory pool where it was obtained from.

The box argument specifies the address of the memory block to be freed.

The box_mem argument specifies the start address of the memory pool where the block was obtained from.

The _free_box function is in the RL-RTX library. The prototype is defined in rtl.h.

Note

  • If you return the memory block to a memory pool that did not provide the memory block, serious memory errors might occur.
  • The _free_box function is reentrant and thread-safe. You can call it from the main function and from an IRQ interrupt function with no restriction.
Return Value The _free_box function returns 0 if the memory block was successfully returned to the memory pool. If there was an error while freeing the block, it returns 1.
See Also _alloc_box, _calloc_box, _init_box
Example 
#include <rtl.h>

/* Reserve a memory for 32 blocks of 20-bytes. */
U32 mpool[32*5 + 3];

void membox_test (void) {
   U8 *box;
   U8 *cbox;

   _init_box (mpool, sizeof (mpool), 20);
   box  = _alloc_box (mpool);
   /* This block is initialized to 0. */
   cbox = _calloc_box (mpool);
    .
    .
   _free_box (mpool, box);
   _free_box (mpool, cbox);
}