From: Jorge Almeida <jjalmeida@gmail.com>
To: musl@lists.openwall.com
Subject: RTC_RD_TIME
Date: Tue, 29 Aug 2017 22:28:14 +0100 [thread overview]
Message-ID: <CAKpSnp+h=YwfNmfMTVCftMhUPEDt8RqeZQDVLVCMLeex9DXLSQ@mail.gmail.com> (raw)
A function to read the hardware clock (the battery powered thingy in
the motherboard):
(man 4 rtc)
void read_hw(struct rtc_time* rtctime){
int rtcfd=open("/dev/rtc0" , O_RDONLY);
ioctl(rtcfd, RTC_RD_TIME, rtctime);
close(rtcfd);
}
(error checking omitted)
The problem:
warning: overflow in implicit constant conversion [-Woverflow]
(an arrow pointing to RTC_RD_TIME)
The same program compiles without warnings with glibc and dietlibc.
Headers:
#define _DEFAULT_SOURCE
#include <unistd.h>
#include <stdlib.h>
#include <stdint.h>
#include <string.h>
#include <sys/types.h>
#include <sys/wait.h>
#include <sys/time.h>
#include <time.h>
#include <linux/unistd.h>
#include <math.h>
#include <sys/ioctl.h>
#include <sys/stat.h>
#include <linux/vt.h>
#include <linux/rtc.h>
#include <fcntl.h>
#include <errno.h>
#include <stdio.h>
TIA
Jorge Almeida
next reply other threads:[~2017-08-29 21:28 UTC|newest]
Thread overview: 6+ messages / expand[flat|nested] mbox.gz Atom feed top
2017-08-29 21:28 Jorge Almeida [this message]
2017-08-30 1:43 ` RTC_RD_TIME Rich Felker
2017-08-30 6:35 ` RTC_RD_TIME Jorge Almeida
2017-08-30 12:55 ` RTC_RD_TIME Alexander Monakov
2017-08-30 15:20 ` RTC_RD_TIME Jorge Almeida
2017-08-30 16:42 ` RTC_RD_TIME Alexander Monakov
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