i´m trying to compile 3 files in C. One is main.c, where i declare the variables, another is cuenta.h and the other is cliente.h. cuenta.h has a struct used in another struct in cliente.h, but this error appears. How can I solve this? Thanks!
cliente.h
#ifndef PACABANK_CLIENTE_H
#define PACABANK_CLIENTE_H
#include "cuenta.h"
#include "fecha.h"
typedef struct {
char *dni;
char *titular;
Tarjeta tarjeta;
}InfoCliente;
cuenta.h
#ifndef PACABANK_CUENTA_H
#define PACABANK_CUENTA_H
#include "cliente.h"
#include "fecha.h"
typedef struct
{
int numero_tarjeta;
char *iban;
Fecha caducidad;
char *nombre_titular;
int cvv;
char *tipo; //mastercard, visa, american express.....
float limite;
}Tarjeta;
The error
In file included from cuenta.h:7:0,
from cuenta.c:5:
cliente.h:14:5: error: unknown type name 'Tarjeta'
Tarjeta tarjeta;
Related
I have a program which is processing list in c, it is working perfectly as long as I have it in one source file, when I try to separate it and compile it got this error “ delete_functions.c:15:13: error: unknown type name ‘nodetype’ ” same error goes for functionality_functions.c and insert_functions.c here is the code
main.c
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include "types.h"
#include "delete_functions.h"
#include "insert_functions.h"
#include "functionality_functions.h"
int main(){
//i did not upload all the main function code because it is way to long
}
types.h
typedef char AirportCode[4];
typedef struct nodetype{
char Airport[4];
struct nodetype *next;
} nodetype;
delete_functions.h
void Delete(nodetype *list,char node[4]);
void DeleteLast(nodetype *list);
functionality_functions.h
void print(nodetype *head);
nodetype *search(nodetype *list,char item[4]);
nodetype *create();
insert_functions.h
void *InsertLast(nodetype *list,char item[4]);
void *InsertAfter(nodetype *list,char item[4],char node[4]);
According to the GCC error message, there error is in the delete_functions.c file.
Presumably, it looks like this at the beginning:
#include "delete_functions.h"
Since delete_functions.h does not itself include types.h, you need to include it first:
#include "types.h"
#include "delete_functions.h"
Alternatively, you can add include guards to your headers so, that they can safely be included multiple times, like this for types.h:
#ifndef TYPES_H
#define TYPES_H
typedef char AirportCode[4];
typedef struct nodetype{
char Airport[4];
struct nodetype *next;
} nodetype;
#endif
And for delete_functions.h:
#ifndef DELETE_FUNCTIONS_H
#define DELETE_FUNCTIONS_H
void Delete(nodetype *list,char node[4]);
void DeleteLast(nodetype *list);
#endif
The *_H include guard macros are necessary because otherwise, main.c would not compile anymore: each type in types.h can only be defined once per translation unit, and without the guards, every *.h would bring in another definition, leading to compiler errors.
I need to build a "social network" for college, but I always get unknown type name 'List' while compiling. I removed a lot of functions from my headers, but I still get the same error and I don't know why.
I've got 3 headers:
My friend's header
#ifndef FRIEND_H
#define FRIEND_H
#include "ListHeadTail.h"
typedef struct Friend{
int id;
struct Friend *nextFriend;
}Friend;
void printFriends(List *l);
void removeFriend(List *l);
void addFriend(List *l);
#endif /* FRIEND_H */
My list header:
#ifndef LISTHEADTAIL_H
#define LISTHEADTAIL_H
#include "Student.h"
typedef struct pStudent{
struct pStudent *ant;
Student *s;
struct pStudent *prox;
}pStudent;
typedef struct list{
pStudent *head;
pStudent *tail;
}List;
void startList(List *l);
void printList(List *l);
void freeList(List *l);
#endif /* LISTHEADTAIL_H */
My student's header
#ifndef STUDENT_H
#define STUDENT_H
#define MAX 51
#include "Friend.h"
#include "ListHeadTail.h"
typedef struct Student{
int id;
char name[MAX];
Friend *friends;
}Student;
Student* readStudent ();
void printStudent(Student* a);
void changeData(List *l);
#endif /* STUDENT_H */
My main:
#include <stdio.h>
#include <stdlib.h>
#include "ListHeadTail.h"
#include "Friend.h"
#include "Student.h"
int main(int argc, char** argv) {
List l;
startList(&l);
freeList(&l);
return (EXIT_SUCCESS);
}
Thanks for reading.
Here's the (first) error I get when I try to compile this set of files:
$ cc main.c
In file included from main.c:4:
In file included from ./ListHeadTail.h:4:
In file included from ./Student.h:6:
./Friend.h:11:19: error: unknown type name 'List'
void printFriends(List *l);
Look at the file names and line numbers. Note that at ListHeadTail.h line 4, you've already defined LISTHEADTAIL_H, but you haven't yet reached the actual declaration of List. You then go into Student.h, and from there into Friend.h. That includes ListHeadTail.h again -- but since LISTHEADTAIL_H is already defined, this include does nothing. So you continue through Friend.h with no declaration of List, and therefore get an error on the declarations that reference it.
As noted by #lurker in their comment, the basic issue here is circular dependency, and a simple fix is forward declaration. In this case, you could simply modify Friend.H, replacing #include "ListHeadTail.h" with typedef struct list List;.
But to me this is a bit hacky. If you shift the order of includes somewhere, the build might break again.
I think the real problem is that the declarations of the functions (printFriends, etc.) don't belong in Friend.h; they belong in ListHeadTail.h. The functions have nothing to do with the Friend type. Sure, they have "Friend" in their names, but the only type referenced in the declarations is List. So they belong in ListHeadTail.h. Same goes for the changeData function in Student.h.
In an object-oriented design (say, in Java), these functions would all probably be methods of the List class, and would be declared in that class's source file.
okay, ive searched a solution for like two days now but i couldnt find whats going wrong with my code. ;(
The task is simple: define a new type using typedef and have a function read out lines of this new type from a file into an array of again this new type. so my typedef inside the headerfile looks like this right now (ive tried several variants of writing this)
// filename: entries.h
#ifndef ENTRIES_H_
#define ENTRIES_H_
#include<time.h>
typedef struct{
char Loginname[25];
time_t RegDate;
unsigned long Highscore;
time_t Hdate;
}typePlayerEntry;
int readPlayerList(char *name, typePlayerEntry *feld);
#endif /* ENTRIES_H_ */
the main.c:
//filename: main.c
#include <stdio.h>
#include "entries.h"
int main(void) {
char name[13]="numbers.txt";
typePlayerEntry *pep;
readPlayerList(name, pep);
return 0;
}
my function file looks like this (and heres where the error is shown)
//filename: readPlayerList.c
int readPlayerList(char *name, typePlayerEntry *feld) {
return 0;
}
irrelevant code is completely left out. The problem is reproducable with the code posted.
the program wont compile because the type of the second argument in the function file could not be recognized,
- which is odd, because its defined in the header file and also usable in the main function.
And this error is somehow connected to the declaration of (in this case) a pointer of type playerEntry in my main.c. So if i do not declare it, theres no error, though i have to declare it to actually give it to the function. how come that the solution so far is to include the entries.h into the readPlayerList.c, which wasnt neccesary for previous functions?
im using eclipse kepler with MinGW, in case thats a compiler issue.
corrected the missing include of time.h and adjusted the code a little.
You are missing #include <time.h> in entries.h.
// filename: entries.h
#ifndef ENTRIES_H_
#define ENTRIES_H_
typedef struct {
char Loginname[25];
time_t RegDate; /* from <time.h> */
unsigned long Highscore;
time_t Hdate; /* from <time.h> */
} playerEntry;
int readPlayerList(char *name, playerEntry *feld);
#endif /* ENTRIES_H_ */
And you need to #include "entries.h" in readPlayerList.c
//filename: readPlayerList.c
int readPlayerList(char *name, typePlayerEntry *feld) {
/* ^^^^^^^^^^^^^^^ from entries.h */
return 0;
}
part of the problem is the compiler is seeing (at least) two different meanings/definitions for the 'playerEntry' name.
Suggest:
1) eliminate the 'typedef' statement
(it is just cluttering the code and confusing the compiler)
2) properly reference the struct via:
'struct playerEntry' instead of 'playerEntry'
in TheHeader.h file:
struct playerEntry
{
char Loginname[25];
time_t RegDate;
unsigned long Highscore;
time_t Hdate;
};
int readPlayerList(char *name, struct playerEntry *feld);
in the source file:
#include "TheHeader.h"
int readPlayerList(char *name, struct playerEntry *feld)
{
return 0;
}
Error 2 error C2371: 'QixC': redefinition; different basic types line 5
Error 5 error C2371: 'QixC': redefinition; different basic types line 5
Error 13 error C2371: 'QixC': redefinition; different basic types line 5
This is the part of the file Game.h:
#include "Graphics_Console.h"
#include <stdio.h>
#include <conio.h>
typedef struct
{
int X;
int Y;
}QixC;
typedef struct
{
int X;
int Y;
}CCursor;
And I use them in Game.c :
#include "Game.h"
#include <stdio.h>
#include <conio.h>
#include <time.h>
int QIX(int nivell)
{
QixC Qix;
CCursor Cursor;
HANDLE hScreen;
int DirQixX,DirQixY;
int IniciX,IniciY;
int FiX, FiY;
int DirStix=0;
int Area=0,AreaTotal=0,AreaObjectiu=(FI_X-INICI_X)*(FI_Y-INICI_Y)*0.75;
int Pantalla=1;
int Puntuacio=0;
int tecla=0;
int viu=1;
int NCops=0, Velocitat=1000/(nivell*0.70);
int XocStix=0;
char continuar[1];
hScreen = GetStdHandle(STD_OUTPUT_HANDLE);
InitScreen(hScreen);
do
{
system("CLS");
IniciX=INICI_X,IniciY=INICI_Y;
FiX=FI_X, FiY=FI_Y;
Cursor.X=INICI_X+(FiX-INICI_Y)/2,Cursor.Y=FI_Y;
DibuixarRectangle(IniciX,IniciY,FI_X,FI_Y,hScreen);
InfoPuntsPartida(hScreen, Puntuacio);
InfoPantallaPartida(hScreen, Pantalla);
Qix.X=Aleatori(IniciX+1,FiX-1),Qix.Y=Aleatori(IniciY+1,FiY-1);
InicialitzarDirQix(&DirQixX,&DirQixY);
PintarQix(Qix,hScreen);
PintarCursor(Cursor.X,Cursor.Y,hScreen);
do{
if(_kbhit())
{
tecla=LlegirEvent();
TractarEvent(tecla,Cursor,&IniciX,&IniciY,&FiX,&FiY,Qix,&DirStix,&Area,hScreen);
if(Area)
{
Puntuacio=Puntuacio+Area;
AreaTotal+=Area;
Area=0;
InfoPuntsPartida(hScreen,Puntuacio);
}
}
NCops++;
if(NCops==Velocitat)
{
if(DirStix!=0)
XocStix=QiXXocStiX(Qix,Cursor,DirStix);
if(!XocStix)
MoureQix(Qix,&DirQixX,&DirQixY,IniciX,IniciY,FiX,FiY,hScreen);
else
viu=0;
NCops=0;
}
}while((tecla!=TECLA_q)&&(tecla!=TECLA_Q)&&viu &&(AreaTotal<AreaObjectiu));
GameOver(hScreen);
TextColor(LIGHTGREY,BLACK,hScreen);
GotoXY(0,FI_Y+1,hScreen);
return Puntuacio;
system ("PAUSE");
printf("Continuar?(s/n)");
scanf("%c",&continuar);
}while(continuar!="s");
}
Sorry for the foreign words and names, english is not my first language.
I can't see where is redefined. They don't appear anywhere else,but are passed as parameters to some functions. Any help, please?
Try guarding your header against multiple inclusion.
#ifndef GAME_H
#define GAME_H
#include "Graphics_Console.h"
#include <stdio.h>
#include <conio.h>
typedef struct
{
int X;
int Y;
}QixC;
typedef struct
{
int X;
int Y;
}CCursor;
#endif /* GAME_H */
By default, if you include multiple headers which directly or indirectly include your header, you'll get multiple competing (if identical) versions of its structures and functions. You can avoid this by starting your header
#ifndef SOMETHING_UNIQUE_TO_YOUR_HEADER
#define SOMETHING_UNIQUE_TO_YOUR_HEADER
and ending it
#endif /* SOMETHING_UNIQUE_TO_YOUR_HEADER */
which guarantees that any source file will include at most a single copy of your structures.
well i'm having difficulties, i cant work with struct pointers in other .c files,
always when i'm passing pointers to structs to functions not in the same .c file as the struct it annoying me with such messages. and also when i can't access struct members of one struct from other .c file i'm g
what am i doing wrong? my includes? that's for example two of my structs .h files:
Server.h :
#ifndef SERVER_H
#define SERVER_H
typedef struct Server_s* Server;
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include "Company.h"
#include "Client.h"
#include "Order.h"
#include "SMSServer.h"
#include "MMSServer.h"
Server InstallServer(CompanyL pcompanyList , ClientL pclientList , OrderL porderList);
void RunServer(Server pmainServer);
void OrdersToDoPerTimestamp(FILE *result , Server pmainServer , int currentTimestamp);
#endif
Client.h :
#ifndef _CLIENT_H
#define _CLIENT_H
typedef struct Client_s* Client;
typedef struct ClientNODE* ClientL;
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include "Server.h"
ClientL InstallClients(CompanyL pcompanyList , char* pfileName);
void AppendClientNode(ClientL pclientList , CompanyL pcompanyList , char* ptelNumber , char* pclientType , char* pclientCredit);
Client FindClient(ClientL pclientList, char* pclientTelNumber);
double getCostAndChargeSMSMessage(Client sourceNumber , Company sourceNumberCompany);
#endif
i can create one struck type in other .c files, but later can't access their members?
please guide me a bit.
If you want to give access struct members to other files, you have to put the full struct definition into the header file. E.g:
#ifndef SERVER_H
#define SERVER_H
struct Server_s {
int id;
};
typedef struct Server_s* Server;
#endif
The definition-less idiom you are currently using is meant to hide the implementation details from outside users: others can pass and receive pointers to the structures, but only the defining file (Server.c) can use the struct members.
You can only access struct members if the definition is available, so you'd have to define it in a header if you want to access them from multiple c files.