From 5e9d03d507aad324a803eb8795e0eed6fb671761 Mon Sep 17 00:00:00 2001 From: guowenxue <guowenxue@gmail.com> Date: Mon, 10 Jul 2023 15:24:52 +0800 Subject: [PATCH] Merge branch 'master' of http://master.iot-yun.club:8088/r/raspberrypi --- apue/1.File_IO/ds18b20.c | 13 ++++++------- 1 files changed, 6 insertions(+), 7 deletions(-) diff --git a/apue/1.File_IO/ds18b20.c b/apue/1.File_IO/ds18b20.c index 1ad5192..0ff2a34 100644 --- a/apue/1.File_IO/ds18b20.c +++ b/apue/1.File_IO/ds18b20.c @@ -45,14 +45,14 @@ int ds18b20_get_temperature(float *temp) { - char w1_path[50] = "/sys/bus/w1/devices/"; + const char *w1_path = "/sys/bus/w1/devices/"; + char ds_path[50]; char chip[20]; char buf[128]; DIR *dirp; struct dirent *direntp; int fd =-1; char *ptr; - float value; int found = 0; int rv = 0; @@ -89,19 +89,18 @@ } /* get DS18B20 sample file full path: /sys/bus/w1/devices/28-xxxx/w1_slave */ - strncat(w1_path, chip, sizeof(w1_path)-strlen(w1_path)); - strncat(w1_path, "/w1_slave", sizeof(w1_path)-strlen(w1_path)); + snprintf(ds_path, sizeof(ds_path), "%s/%s/w1_slave", w1_path, chip); /* open file /sys/bus/w1/devices/28-xxxx/w1_slave to get temperature */ - if( (fd=open(w1_path, O_RDONLY)) < 0 ) + if( (fd=open(ds_path, O_RDONLY)) < 0 ) { - printf("open %s error: %s\n", w1_path, strerror(errno)); + printf("open %s error: %s\n", ds_path, strerror(errno)); return -4; } if(read(fd, buf, sizeof(buf)) < 0) { - printf("read %s error: %s\n", w1_path, strerror(errno)); + printf("read %s error: %s\n", ds_path, strerror(errno)); rv = -5; goto cleanup; } -- Gitblit v1.9.1