update posix-info.txt
+ tolower()
+ toupper()
-<errno.h> -> for gcc, keil, iar platform at the same time;
- Suggest to choose <sys/errno.h>
+<errno.h> -> Suggesting to use <sys/errno.h> instead of <errno.h> to be compatible with three compilation platforms of IAR Keil GCC at the same time.
+ errno
<fcntl.h>
+ longjmp()
+ setjmp()
-<signal.h> -> for gcc, keil, iar platform at the same time;
- Suggest to choose <sys/signal.h>
+<signal.h> -> Suggesting to use <sys/signal.h> instead of <signal.h> to be compatible with three compilation platforms of IAR Keil GCC at the same time.
+ kill()
+ pthread_kill()
+ pthread_sigmask()
+ fflush()
+ fgetc()
+ fgets()
-- fileno()
++ fileno() ; GCC and IAR support, but Keil doesn't support
- flockfile()
+ fopen()
+ fprintf()
<sys/utsname.h>
+ uname()
-<time.h> -> for gcc, keil, iar platform at the same time;
- Suggest to choose <sys/time.h>
+<time.h> -> Suggesting to use <sys/time.h> instead of <time.h> to be compatible with three compilation platforms of IAR Keil GCC at the same time.
+ asctime()
+ asctime_r()
+ clock_getres()
+ timer_getoverrun()
+ timer_gettime()
+ timer_settime()
-% tzname ; you should better use 'tz_xxx' in the rt-thread.
-% tzset() ; you should better use 'tz_xxx' in the rt-thread.
+- tzname ; you should better use 'tz_xxx' in the rt-thread.
+- tzset() ; you should better use 'tz_xxx' in the rt-thread.
<unistd.h>
+ alarm()
