كيفية حل تحذير وظيفة المكتبة المعلنة ضمنيًا في لغة سي

تعرف على كيفية حل تحذير وظيفة المكتبة المعلنة ضمنيًا في لغة سي

عند تجميع ملفجقد تجد أن المترجم يعطيك تحذيرًا مشابهًا لـ

hello.c:6:3: warning: implicitly declaring library function
      'printf' with type 'int (const char *, ...)'
      [-Wimplicit-function-declaration]
  printf("Name length: %u", length);
  ^

or

hello.c:5:16: warning: implicitly declaring library function
      'strlen' with type 'unsigned long (const char *)'
      [-Wimplicit-function-declaration]
  int length = strlen(name);
               ^

This problem occurs because you used a function from the standard library without first including the appropriate header file.

The compiler will also give you a suggestion, like the following one:

hello.c:5:16: note: include the header <string.h> or
      explicitly provide a declaration for 'strlen'

which points you in the right direction.

In this case, adding

#include <stdio.h>

at the top of the C file will solve the issue.

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