59 lines
1.5 KiB
C
59 lines
1.5 KiB
C
/**
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* Copyright 2015 University of Applied Sciences Western Switzerland / Fribourg
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*
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* Licensed under the Apache License, Version 2.0 (the "License");
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* you may not use this file except in compliance with the License.
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* You may obtain a copy of the License at
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*
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* http://www.apache.org/licenses/LICENSE-2.0
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*
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* Unless required by applicable law or agreed to in writing, software
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* distributed under the License is distributed on an "AS IS" BASIS,
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* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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* See the License for the specific language governing permissions and
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* limitations under the License.
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*
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* Module: MA-CSEL1 - Building Embedded Systems under Linux
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*
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* Abstract: Introduction to the Embedded Linux Development Environment
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*
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* Purpose: System call demo program
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* call this demo program with
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* # strace ./app_a
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*
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* Autĥor: Daniel Gachet
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* Date: 28.08.2015
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*/
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#include <sys/types.h>
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#include <sys/stat.h>
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#include <fcntl.h>
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#include <unistd.h>
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#include <dirent.h>
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#include <errno.h>
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#include <libgen.h>
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#include <stdio.h>
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#include <string.h>
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#include <stdlib.h>
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int main()
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{
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int temp = 99000;
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int f = open("/sys/class/thermal/thermal_zone0/temp", O_RDONLY);
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if (f >= 0) {
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char val[50] = "";
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ssize_t r = read (f, val, sizeof(val));
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close (f);
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if (r > 0) {
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temp = atoi(val);
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}
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}
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printf ("current temperature: %d.%02d degree Celcius\n",
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temp/1000, (temp/10)%100);
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return 0;
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}
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