Using SD card with portenta

Thank you, now I can read and write from sdcard.
But now I am trying to run my code but I got on this error, Why? I have not any sleep function in my code!!

In file included from c:\users\lab\appdata\local\arduino15\packages\arduino\tools\arm-none-eabi-gcc\7-2017q4\arm-none-eabi\include\sys\reent.h:13:0,
                 from c:\users\lab\appdata\local\arduino15\packages\arduino\tools\arm-none-eabi-gcc\7-2017q4\arm-none-eabi\include\math.h:5,
                 from c:\users\lab\appdata\local\arduino15\packages\arduino\tools\arm-none-eabi-gcc\7-2017q4\arm-none-eabi\include\c++\7.2.1\cmath:45,
                 from c:\users\lab\appdata\local\arduino15\packages\arduino\tools\arm-none-eabi-gcc\7-2017q4\arm-none-eabi\include\c++\7.2.1\math.h:36,
                 from C:\Users\lab\AppData\Local\Arduino15\packages\arduino\hardware\mbed_portenta\4.1.1\cores\arduino/mbed/targets/TARGET_STM/TARGET_STM32H7/STM32Cube_FW/STM32H7xx_HAL_Driver/stm32h7xx_hal_def.h:33,
                 from C:\Users\lab\AppData\Local\Arduino15\packages\arduino\hardware\mbed_portenta\4.1.1\cores\arduino/mbed/targets/TARGET_STM/TARGET_STM32H7/STM32Cube_FW/STM32H7xx_HAL_Driver/stm32h7xx_hal_rcc.h:29,
                 from C:\Users\lab\AppData\Local\Arduino15\packages\arduino\hardware\mbed_portenta\4.1.1\cores\arduino/mbed/targets/TARGET_STM/TARGET_STM32H7/STM32Cube_FW/stm32h7xx_hal_conf.h:398,
                 from C:\Users\lab\AppData\Local\Arduino15\packages\arduino\hardware\mbed_portenta\4.1.1\cores\arduino/mbed/targets/TARGET_STM/TARGET_STM32H7/STM32Cube_FW/STM32H7xx_HAL_Driver/stm32h7xx_hal.h:30,
                 from C:\Users\lab\AppData\Local\Arduino15\packages\arduino\hardware\mbed_portenta\4.1.1\cores\arduino/mbed/targets/TARGET_STM/TARGET_STM32H7/STM32Cube_FW/CMSIS/stm32h7xx.h:223,
                 from C:\Users\lab\AppData\Local\Arduino15\packages\arduino\hardware\mbed_portenta\4.1.1\cores\arduino/mbed/targets/TARGET_STM/TARGET_STM32H7/cmsis.h:22,
                 from C:\Users\lab\AppData\Local\Arduino15\packages\arduino\hardware\mbed_portenta\4.1.1\cores\arduino/mbed/targets/TARGET_STM/PinNamesTypes.h:33,
                 from C:\Users\lab\AppData\Local\Arduino15\packages\arduino\hardware\mbed_portenta\4.1.1\variants\PORTENTA_H7_M7/pinmode_arduino.h:24,
                 from C:\Users\lab\AppData\Local\Arduino15\packages\arduino\hardware\mbed_portenta\4.1.1\cores\arduino/Arduino.h:26,
                 from sketch\portenta.ino.cpp:1:
c:\users\lab\appdata\local\arduino15\packages\arduino\tools\arm-none-eabi-gcc\7-2017q4\arm-none-eabi\include\sys\unistd.h:209:10: error: conflicting declaration of C function 'unsigned int sleep(unsigned int)'
 unsigned _EXFUN(sleep, (unsigned int __seconds ));
          ^
In file included from C:\Users\lab\AppData\Local\Arduino15\packages\arduino\hardware\mbed_portenta\4.1.1\cores\arduino/mbed/drivers/include/drivers/HighResClock.h:22:0,
                 from C:\Users\lab\AppData\Local\Arduino15\packages\arduino\hardware\mbed_portenta\4.1.1\cores\arduino/mbed/mbed.h:82,
                 from C:\Users\lab\AppData\Local\Arduino15\packages\arduino\hardware\mbed_portenta\4.1.1\cores\arduino/mbed.h:8,
                 from C:\Users\lab\AppData\Local\Arduino15\packages\arduino\hardware\mbed_portenta\4.1.1\libraries\Portenta_SDCARD\src/SDMMCBlockDevice.h:21,
                 from C:\Users\lab\Desktop\portenta\portenta.ino:12:
C:\Users\lab\AppData\Local\Arduino15\packages\arduino\hardware\mbed_portenta\4.1.1\cores\arduino/mbed/platform/include/platform/mbed_power_mgmt.h:195:20: note: previous declaration 'void sleep()'
 static inline void sleep(void)
                    ^~~~~
exit status 1
Error compiling for board Arduino Portenta H7.