c - reading uart software on mcu - code understanding -


below code in uart driver header file performing non blocking read on uart interface. 

/**  * perform single character read uart interface.  * blocking synchronous call.  *  * @brief uart character data read.  * @param [in] uart uart index.  * @param [out] data data read uart.  * @return ti_uart_status_t returns uart specific return code.  */  ti_uart_status_t ti_uart_read(const ti_uart_t uart, uint8_t *data);

below example code uses above function character uart interface. i'm trying understand it.

i of thought ti_uart_read() reads character uart interface, hence why there need getcharacter()?

also why necessary pass &c function? function?

many 

int getcharacter(void) { uint8_t c = 0; int ret;   ret = ti_uart_read(ti_uart_0, &c);   if (ti_rc_ok == ret) {     return ((int) c);   }   return -1; }

the function getcharacter wrapper the uart function ti_uart_read, handles operation's status getting byte. ti_uart_read supplies 2 items of data: status of operation, , value read. acheive status returned function value, , data set pointer. reason done way round, smoother , more idiomatic program logic can achieved if checking function's return value. library functions manage in one; fgetc 1 example. getcharacter works in similar way: returns -1 (data didn't expect) in case of error.


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