c - struct intitialization notation not working with heap allocated storage -

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with gcc (gcc) 4.4.6 , try compile program - 

  1 #include <stdio.h>   2 #include <stdlib.h>   3    4 int main(int argc, char *argv[])   5 {   6    7     struct b {   8         int i;   9         char ch;  10     };  11   12     struct b *ptr;  13   14     ptr = (struct b*) calloc(1, sizeof(struct b));  15   16     *ptr = {  17         .i = 10,  18         .ch = 'c',  19     };  20   21     printf("%d,%c\n", ptr->i, ptr->ch);  22   23     return 0;  24 }  25   $ make gcc -g -wall -o test test.c  test.c: in function ‘main’: test.c:16: error: expected expression before ‘{’ token make: *** [test] error 1 

*ptr = {    .i = 10,    .ch = 'c', };

this usage called designated initializer, name implies, it's used initialize struct or arrays, trying assigning.

the correct usage of designated initializer:

strcut b foo = {.i = 10, .ch = 'c'};

to assign struct, still need use:

 ptr->i = 10;  ptr->ch = 'c';

edit: or can use compound literal in @andrey t's answer:

*ptr = (struct b) {   .i = 10,   .ch = 'c', };

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