写了一段代码尝试获取主机主频信息:
double get_cpu_info(){
double cpuclockrate;
FILE *fp;
char str[81];
if(fp=popen("cat /proc/cpuinfo|grep cpu\\ MHz|sed -e 's/.*:[^0-9]//'","r")==NULL){
printf("无法读取CPU主频信息\n");
}else{
fgets(str,80,fp);
double spd=atof(str);
cpuclockrate = spd;
pclose(fp);
}
return cpuclockrate;
}
make编译提醒我没有对popen函数进行声明。
[root@iZ2ze2y6fwj9mvujtsiya4Z test_mem]# make
gcc -c systeminfo.c
systeminfo.c: In function ‘get_cpu_info’:
systeminfo.c:56:10: warning: assignment makes pointer from integer without a cast [enabled by default]
if(fp=popen("cat /proc/cpuinfo|grep cpu\\ MHz|sed -e 's/.*:[^0-9]//'","r")==NULL){
^
gcc -o main main.o systeminfo.o cpuusage.o