codeblocks - C - get character issue -

when run following code:

#include <stdio.h> #include <stdlib.h>   int main() {     int n;     char y;      printf("message\n");     fscanf(stdin, "%c", &y);      printf("message\n");     fscanf(stdin, "%c", &y);      return 0; } 

i this:

message {enter character} message 

the problem not asked enter character twice if there 2 scanf functions. output should this:

message {enter character} message {enter character} 

i have issue getc() too:

#include <stdio.h> #include <stdlib.h>   int main() {     int n;     char y;      printf("message\n");     y=getc(stdin);      printf("message\n");     y=getc(stdin);      return 0; } 

also, fflush() not help:

#include <stdio.h> #include <stdlib.h>   int main() {     int n;     char y;      printf("message\n");     y=getc(stdin);      fflush(stdin);     fflush(stdout);      printf("message\n");     y=getc(stdin);      return 0; } 

i've tried fflush stdin, stdout, stdin+stdout (at same time), result still same.

change

fscanf(stdin, "%c", &y); 

to

fscanf(stdin, " %c", &y); 

quoting c11 standard:

7.21.6.2 fscanf function

[...]

5. a directive composed of white-space character(s) executed reading input first non-white-space character (which remains unread), or until no more characters can read. directive never fails.

so, space before %c discards \n character left on first fscanf. did character come from? recall press enter key after enter character. character not consumed first fscanf , stays in standard input buffer(stdin).

this happens in second version of program,i.e, second getc gets newline character left on first one. can use following code flush(clear) stdin:

int c; while((c=getchar())!=eof && c!='\n'); 

as why fflush(stdin); dosen't work standard says behavior undefined:

7.21.5.2 fflush function

[...]

2. if stream points output stream or update stream in recent operation not input, fflush function causes unwritten data stream delivered host environment written file; otherwise, behavior undefined.

but note fflush(stdin) does work in implementations. read this