Passing structure to function in C

 

Passing structure to function in C:

It can be done in below 3 ways.

1. Passing structure to a function by value
2. Passing structure to a function by address(reference)
3. No need to pass a structure – Declare structure variable as global

Example program – passing structure to function in C by value:

In this program, the whole structure is passed to another function by value. It means the whole structure is passed to another function with all members and their values. So, this structure can be accessed from called function. This concept is very useful while writing very big programs in C.

C

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#include <stdio.h> #include <string.h>   struct student {             int id;             char name[20];             float percentage; };   void func(struct student record);   int main() {             struct student record;               record.id=1;             strcpy(record.name, "Raju");             record.percentage = 86.5;               func(record);             return 0; }   void func(struct student record) {             printf(" Id is: %d \n", record.id);             printf(" Name is: %s \n", record.name);             printf(" Percentage is: %f \n", record.percentage); }

COMPILE & RUN

Output:

Id is: 1 Name is: Raju Percentage is: 86.500000

Example program – Passing structure to function in C by address:

In this program, the whole structure is passed to another function by address. It means only the address of the structure is passed to another function. The whole structure is not passed to another function with all members and their values. So, this structure can be accessed from called function by its addres

C

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#include <stdio.h> #include <string.h>   struct student {            int id;            char name[20];            float percentage; };   void func(struct student *record);   int main() {           struct student record;             record.id=1;           strcpy(record.name, "Raju");           record.percentage = 86.5;             func(&record);           return 0; }   void func(struct student *record) {           printf(" Id is: %d \n", record->id);           printf(" Name is: %s \n", record->name);           printf(" Percentage is: %f \n", record->percentage); }

COMPILE & RUN

Output:

Id is: 1 Name is: Raju Percentage is: 86.500000

Example program to declare a structure variable as global in C:

Structure variables also can be declared as global variables as we declare other variables in C. So, When a structure variable is declared as global, then it is visible to all the functions in a program. In this scenario, we don’t need to pass the structure to any function separately.

C

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#include <stdio.h> #include <string.h>   struct student {             int id;             char name[20];             float percentage; }; struct student record; // Global declaration of structure   void structure_demo();   int main() {             record.id=1;             strcpy(record.name, "Raju");             record.percentage = 86.5;               structure_demo();             return 0; }   void structure_demo() {             printf(" Id is: %d \n", record.id);             printf(" Name is: %s \n", record.name);             printf(" Percentage is: %f \n", record.percentage); }

COMPILE & RUN

Output:

Id is: 1 Name is: Raju Percentage is: 86.500000

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