在非常基本的 C 程序上使用 GDB 进行温度转换时出现错误 "printf.c: No such file or directory"

Question

这就是 GDB 向我展示的内容

(gdb) break main
Breakpoint 1 at 0x722: file homework1.c, line 4.
(gdb) run
Starting program: /home/aj_the_kid/ECE_373/homework1 
Breakpoint 1, main () at homework1.c:4
4   {
(gdb) step
8     printf("Enter the temperature (for conversion) in Fahrenheit:  ");
(gdb) step
__printf (
    format=0x555555554838 "Enter the temperature (for conversion) in Fahrenheit:  ") at printf.c:28
28  printf.c: No such file or directory.
(gdb) bt
 #0  __printf (
    format=0x555555554838 "Enter the temperature (for conversion) in Fahrenheit:  ") at printf.c:28
 #1  0x0000555555554742 in main () at homework1.c:8
(gdb) next
32  in printf.c
(gdb) next
33  in printf.c
(gdb) step
_IO_vfprintf_internal (s=0x7ffff7dd0760 <_IO_2_1_stdout_>, 
    format=0x555555554838 "Enter the temperature (for conversion) in Fahrenheit:  ", ap=ap@entry=0x7fffffffde20) at vfprintf.c:1244
1244    vfprintf.c: No such file or directory.
(gdb) step
1275    in vfprintf.c

这是我的 Linux

#include <stdio.h>

int main()
{
  float temp_F, temp_C;

  // Prompt user for input (i.e. temp in Fahrenheit)
  printf("Enter the temperature (for conversion) in Fahrenheit:  ");
  scanf("%f\n", &temp_F);

  // Convert F to C
  temp_C = (temp_F - 32) * (5/9);
  printf("The temperature in Celsius is: %.2f\n", temp_C);

  return 0;

}

编辑：固定代码以支持浮点型运算

但我仍然遇到问题，它要求我在空行中再次输入华氏度，就像它第一次没有捕获用户输入一样

终端视图

aj_the_kid@AJs-Sandbox:~/ECE_373$ rm file1
aj_the_kid@AJs-Sandbox:~/ECE_373$ gcc -g -o file1 file1.c
aj_the_kid@AJs-Sandbox:~/ECE_373$ ./file1
Enter the temperature (for conversion) in Fahrenheit:  32

32
The temperature in celcius is: 0.00
aj_the_kid@AJs-Sandbox:~/ECE_373$

Answer 1

来自评论：

来自 gdb vfprintf.c: No such file or directory 的错误消息是由于您正试图进入一个您没有源代码的库函数。

计算中的问题是除法(5/9)是作为整数除法执行的。所以结果是 0。这可以通过更改为 (5.0/9.0)

来解决

而scanf问题是由于格式字符串末尾的\n引起的。 scanf 对空格有点奇怪。将 \n 放在格式字符串的末尾会告诉 scanf 跳过所有空格，直到用户键入非空格字符并按回车键。您可以通过删除 \n

来修复它

在非常基本的 C 程序上使用 GDB 进行温度转换时出现错误 "printf.c: No such file or directory"

Getting an error that states "printf.c: No such file or directory" while using GDB on a very basic C program for temperature conversion

c

linux

debugging

gdb

lib