PMbus access

1st byte of rtn is length and last byte is for nothing if you want to read 9bytes data, you need to specify length 11 in i2c master write-read command, when length is set to 0, BMC will perform i2c write.

gcc object file linking

gcc -c xxx.c --> automatically generate xxx.o gcc yyy.c xxx.o --> automatically generate a.out You can use functions defined in xxx.c without including any header files in yyy.c