Char array declaration and initialization in C

Question

I was curious about why this is not allowed in C   char myarray 4    myarray    abc     And this is allowed   char myarray 4     abc     I know that in the first case I should use strcpy   char myarray 4    strcpy myarray   abc      But why declaration and later initialization is not allowed and declaration and simultaneous initialization is allowed  Does it relate to memory mapping of C programs   Thanks

User · Answer

Yes  this is a kind of inconsistency in the language   The     in myarray    abc   is assignment  which won t work as the array is basically a kind of constant pointer   whereas in char myarray 4     abc   it s an initialization of the array  There s no way for  late initialization    You should just remember this rule

User · Answer

That s because your first code snippet is not performing initialization  but assignment   char myarray 4     abc       Initialization   myarray    abc               Assignment    And arrays are not directly assignable in C   The name myarray actually resolves to the address of its first element   amp myarray 0    which is not an lvalue  and as such cannot be the target of an assignment

User · Answer

myarray    abc        is the assignation of a pointer on  abc  to the pointer myarray   This is NOT filling the myarray buffer with  abc    If you want to fill the myarray buffer manually  without strcpy    you can use   myarray 0     a   myarray 1     b   myarray 2     c   myarray 3    0    or  char  ptr   myarray   ptr      a    ptr      b    ptr      c    ptr   0    Your question is about the difference between a pointer and a buffer  an array   I hope you now understand how C addresses each kind

User · Answer

I think these are two really different cases  In the first case memory is allocated and initialized in compile-time  In the second - in runtime

User · Answer

This is another C example of where the same syntax has different meanings  in different places   While one might be able to argue that the syntax should be different for these two cases  it is what it is  The idea is that not that it is  not allowed  but that the second thing means something different  it means  pointer assignment

[c] Char array declaration and initialization in C

Examples related to c

Examples related to arrays

Examples related to char