Determine the number of characters waiting to be read
#include <sys/ioctl.h> #define FIONREAD _IOR('f', 127, int)
Argument | Value |
---|---|
fd | A file descriptor that you obtained by opening the device |
request | FIONREAD |
Additional argument | A pointer to an int |
This command determine the number of characters waiting to be read. It's also implemented as the DCMD_CHR_ISCHARS devctl() command.
None.
The number of characters.