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@ -26,20 +26,28 @@
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#include <stdlib.h>
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#include <unistd.h>
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// 定义程序的主函数,接收命令行参数个数(argc)和参数值(argv)
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int main(int argc, char** argv) {
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char buf[8];
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if (read(0, buf, 8) < 1) {
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printf("Hum?\n");
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exit(1);
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}
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if (buf[0] == '0')
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printf("Looks like a zero to me!\n");
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else
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printf("A non-zero value? How quaint!\n");
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exit(0);
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// 定义一个字符数组buf,大小为8,用于存储从标准输入读取的数据
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char buf[8];
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// 尝试从文件描述符0(标准输入)读取最多8个字节的数据到buf中
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if (read(0, buf, 8) < 1) {
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// 如果读取的字节数小于1(即读取失败),则打印消息并退出程序
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printf("Hum?\n");
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exit(1);
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}
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// 检查buf的第一个字符是否为'0'
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if (buf[0] == '0')
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// 如果是'0',则打印一条消息表示检测到零值
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printf("Looks like a zero to me!\n");
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else
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// 如果不是'0',则打印一条消息表示检测到非零值
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printf("A non-zero value? How quaint!\n");
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// 正常退出程序
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exit(0);
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}
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