c - 使用函数 strcmp 比较指针和字符串

Question

这是我的代码:

  printf("Please input a command\n");

  char *input;
  input = malloc(sizeof(char) * 50);

  if(fgets(input, 50, stdin) != NULL) {
    if(strcmp(input, "end\0") == 0) {
      printf("END");
    }
  }

由于某种原因，当我输入“end”时，它不会打印“END”。这里导致循环条件失败的问题是什么？ strcmp(input, "end\0") == 0当输入指针等于 "end\0" 时应返回 0 ？我也尝试过strcmp(input, "end") == 0这也行不通。我该如何解决这个问题？

Answer 1

fgets包括换行符。使用strcmp(input, "end\n")

来自文档:

Reads characters from stream and stores them as a C string into str until (num-1) characters have been read or either a newline or the end-of-file is reached, whichever happens first.

A newline character makes fgets stop reading, but it is considered a valid character by the function and included in the string copied to str.

正如评论中提到的，您不需要包含 \0当使用字符串文字时。将自动添加空终止符。