Can't make Structures to work in C (Using GCC)

Question

So I was just practicing Structures in C and I encountered a big problem... I am attaching the code and the errors The code I was trying to run is to put a predefined value in the structure and then print it.

Code

#include <stdio.h>
struct student
{
    int sroll;
    char sname[20];
    int stotal;
}
int main()
{
    struct student st;
    clrscr();
    st.sroll = 1;
    strcpy(sname, "Example");
    st.stotal = 700
    printf("\n Roll => %d", st.sroll);
    printf("\n Name => %d", st.sname);
    printf("\n Total Marks => %d", st.stotal);
    return 0;
}

Errors

$ gcc -o strpre strpre.c
strpre.c:8:1: error: expected ‘;’, identifier or ‘(’ before ‘int’
    8 | int main()
      | ^~~
strpre.c: In function ‘main’:
strpre.c:11:5: warning: implicit declaration of function ‘clrscr’ [-Wimplicit-function-declaration]
   11 |     clrscr();
      |     ^~~~~~
strpre.c:13:5: warning: implicit declaration of function ‘strcpy’ [-Wimplicit-function-declaration]
   13 |     strcpy(sname, "Example");
      |     ^~~~~~
strpre.c:13:5: warning: incompatible implicit declaration of built-in function ‘strcpy’
strpre.c:2:1: note: include ‘<string.h>’ or provide a declaration of ‘strcpy’
    1 | #include <stdio.h>
  +++ |+#include <string.h>
    2 | struct student
strpre.c:13:12: error: ‘sname’ undeclared (first use in this function); did you mean ‘rename’?
   13 |     strcpy(sname, "Example");
      |            ^~~~~
      |            rename
strpre.c:13:12: note: each undeclared identifier is reported only once for each function it appears in
strpre.c:14:20: error: expected ‘;’ before ‘printf’
   14 |     st.stotal = 700
      |                    ^
      |                    ;
   15 |     printf("\n Roll => %d", st.sroll);
      |     ~~~~~~          
strpre.c:16:25: warning: format ‘%d’ expects argument of type ‘int’, but argument 2 has type ‘char *’ [-Wformat=]
   16 |     printf("\n Name => %d", st.sname);
      |                        ~^   ~~~~~~~~
      |                         |     |
      |                         int   char *
      |                        %s

By the way, I am using CS50 IDE with the latest GCC version.

EDIT: After I tried @Robert 's fix... Its still not working... https://pastebin.ubuntu.com/p/mBjkR292wb/ EDIT 2: My bad didn't add the semicolons

Do you mean `strcpy(st.sname, "Example");` instead of `strcpy(sname, "Example");`?, also, you want a semicolon after the `struct` definition (Line 7). Finally, `#include ` in order to use `clrscr()`. — David Ranieri, Jan 21 '21 at 09:02

Robert · Answer 1 · 2021-01-21T09:08:58.790

3

I think you missed a semicolon:

struct student
{
    int sroll;
    char sname[20];
    int stotal;
}; // <========================= missing ;

As written in the comments, you also have another mispell:

strcpy(st.sname, "Example");

edited Jan 21 '21 at 09:08

answered Jan 21 '21 at 09:02

Robert

2,711
7
15

Ah ok... Missed it :p – Otus9051 Jan 21 '21 at 09:04
2

When you miss a semicolon after structure declaration in C or class declaration in C++, the error messages from GCC does not make a lot of sense and are very difficult to analyze. – Robert Jan 21 '21 at 09:07
2

Another typo: `st.stotal = 700`: you need a semicolon, you don't like them too much huh? – David Ranieri Jan 21 '21 at 09:12
why doesnt gcc add them by itself... duh. – Otus9051 Jan 21 '21 at 09:13
BTW you also forgot `#include ` – Jabberwocky Jan 21 '21 at 09:16
wait https://pastebin.ubuntu.com/p/7qFHnJCfsp/ – Otus9051 Jan 21 '21 at 09:19
@SteveWhoLikesLinux yes, you have set a world record for errors per line :P you need to `#include `, but you state that you are on `gcc` (or do you mean `MinGW`?), on Linux `conio` doesn't exist, take a look to the clear functions of `ncurses` or use console codes: https://stackoverflow.com/q/17271576/1606345 – David Ranieri Jan 21 '21 at 09:25

Can't make Structures to work in C (Using GCC)

1 Answers1