整理代码片段
根据pid获取进程名
void get_process_name_by_pid(int pid, char *name)
{
char buf[256] = {0};
char path[256] = {0};
sprintf(buf, "/proc/%d/exe", pid);
readlink(buf, path, sizeof(path));
char *filename = basename(path);
strcpy(name, filename);
}C语言变长数组
C99标准才有的特性
void test_vla(const char *str)
{
int len = strlen(str);
char a[len + 1];
memset(a, 0, sizeof(a));
strcpy(a, str);
printf("%s\n", a);
}确保路径存在
bool besure_path(const char *pathname) {
int len = strlen(pathname);
char buffer[len + 1];
memset(buffer, 0, sizeof(buffer));
strcpy(buffer, pathname);
for (int i = 0; i < len; ++i) {
if (buffer[i] == '/') {
buffer[i] = 0;
if (access(buffer, F_OK) < 0) {
if (mkdir(buffer, 0755) < 0) {
return false;
}
}
buffer[i] = '/';
}
}
return true;
}计算一个数字二进制格式1的个数
int count_bit(int n) {
int count = 0;
while (n != 0) {
++count;
n &= n - 1;
}
return count;
}