C/C++总结一

获取参数getopt(), 头文件

getopt(argc, argv, "g:r"); // 参数g/r 附加参数带：，-g 10, -r
...
sscanf(optarg, "%s", counter); //获取附加参数，counter = 10

char[]复制拼接拼接

strcpy(file_path, path1);
strcat(file_path, path2);

配置读取config.txt

FILE *pfile;
pfile = fopen("./config.txt", "r");
fscanf(pfile, "%s", config->para1);//第一行
fscanf(pfile, "%s", config->para2);//第二行
fclose(pfile);

获取文件大小

pfile = fopen("./config.txt", "r");
fseek(pfile, 0L, SEEK_END); //ptr to end
length = ftell(pfile);
fseek(pfile, 0L, SEEK_SET); //ptr to start

byte/char bit翻转

input = ((input&0xaa)>>1)|((input&0x55)<<1);
input = ((input&0xcc)>>2)|((input&0x33)<<2);
input = ((input&0xf0)>>4)|((input&0x0f)<<4);

程序计时 clock_t

time_start = clock();
process();
duration= clock()-time_start;
ms = diff*1000/CLOCKS_PER_SEC; // accuracy us