/*

Employee Record Base

*/

#include<stdio.h>

#include<stdlib.h>

typedef struct employee_rec

} emp_rec;

long record_search(FILE * fp, int emp_no)

{

emp_rec ser_emp;

fseek(fp,0,SEEK_SET);

while(!feof(fp))

{

fread(&ser_emp,sizeof(emp_rec),1,fp);

if(ser_emp.emp_no==emp_no)

return ftell(fp)-sizeof(emp_rec);

}

return -1;

}

void record_insert(FILE * fp,FILE * eno)

{

emp_rec newemp;

int new_emp_no=0;

fread(&new_emp_no,sizeof(int),1,eno);

new_emp_no++;

fseek(fp,0,2);

printf("New Employee number:%d\n",new_emp_no);

newemp.emp_no=new_emp_no;

printf("Enter the name of the employee:");

getchar();

fgets(newemp.emp_name,sizeof(newemp.emp_name),stdin);

printf("Enter the salary of the employee:");

scanf("%lf",&(newemp.emp_sal));

printf("Enter the address of the employee:");

getchar();

scanf("%[^\n]s",newemp.emp_add);

printf("Enter the mobile no of the employee:");

getchar();

scanf("%[^\n]s",newemp.emp_mobile);

fwrite(&newemp,sizeof(emp_rec),1,fp);

fseek(eno,0,0);

fwrite(&new_emp_no,sizeof(int),1,eno);

fseek(eno,0,0);

}

void record_delete(FILE * fp, FILE * delemp)

{

emp_rec del_emp;

int emp_no;

long pos;

printf("Enter the employee number for deletion:");

scanf("%d",&emp_no);

pos=record_search(fp,emp_no);

if(pos!=-1)

{

fseek(fp,pos,SEEK_SET);

del_emp.emp_no=-1;

fwrite(&del_emp,sizeof(emp_rec),1,fp);

fseek(delemp,0,SEEK_END);

fwrite(&emp_no,sizeof(int),1,delemp);

fwrite(&pos,sizeof(long),1,delemp);

}

}

void record_update(FILE * fp)

{

emp_rec upd_emp;

int emp_no,c=0;

long pos;

printf("Enter the employee no for update:");

scanf("%d",&emp_no);

pos=record_search(fp,emp_no);

if(pos !=-1)

{

fseek(fp,pos,SEEK_SET);

fread(&upd_emp,sizeof(emp_rec),1,fp);

printf("\t\t\tDetails of Employee No: %d\n",upd_emp.emp_no);

printf("\tEmployee Name:%s\n",upd_emp.emp_name);

printf("\tEmployee Salary:%lf",upd_emp.emp_sal);

printf("\tEmployee Address:%s\n",upd_emp.emp_add);

printf("\tEmployee Mobile:%s\n",upd_emp.emp_mobile);

printf("Do you want to update Name?\n1. For Yes \n2. For No\n:");

scanf("%d",&c);

getchar();

if(c==1)

scanf("%[^\n]s",upd_emp.emp_name);

printf("Do you want to update Salary?\n1. For Yes \n2. For No\n:");

scanf("%d",&c);

getchar();

if(c==1)

scanf("%lf",&upd_emp.emp_sal);

printf("Do you want to update Address?\n1. For Yes \n2. For No\n:");

scanf("%d",&c);

getchar();

if(c==1)

scanf("%[^\n]s",upd_emp.emp_add);

printf("Do you want to update Mobile?\n1. For Yes \n2. For No\n:");

scanf("%d",&c);

getchar();

if(c==1)

scanf("%[^\n]s",upd_emp.emp_mobile);

fseek(fp,-sizeof(emp_rec),SEEK_CUR);

fwrite(&upd_emp,sizeof(emp_rec),1,fp);

}

}

void menu()

{

emp_rec ser_emp;

int c=0,emp_no;

long pos;

FILE * fp,* eno,* delemp;

if((fp=fopen("emp.dat","rb+"))==NULL)

{

printf("Error 1: Problem with main file opening.\n");

exit(ferror(fp));

}

if((eno=fopen("empno.dat","rb+"))==NULL)

{

printf("Error 2: Problem with employee no file.\n");

exit(ferror(fp));

}

if((delemp=fopen("delemp.dat","rb+"))==NULL)

{

printf("Error 3: Problem with deleted employee file.\n");

delemp=fopen("delemp.dat","wb+");

}

while(c!=6)

{

printf("\t\t\t\t Menu for Employee Record Base\n");

printf("\t\t\t1.Employee Record Insertion\n");

printf("\t\t\t2.Employee Record Search\n");

printf("\t\t\t3.Employee Record Update\n");

printf("\t\t\t4.Employee Record Delete\n");

printf("\t\t\t5.Display All Employees\n");

printf("\t\t\t6.Exit the program.\n");

printf("\t\t\t\t Enter your choice:");

scanf("%d",&c);

switch(c)

{

case 1:

record_insert(fp,eno);

break;

case 2:

printf("Enter the employee no to search:");

scanf("%d",&emp_no);

if((pos=record_search(fp,emp_no))==-1)

printf("Employee does not exist.\n");

else

{

printf("Employee exists.\n");

fseek(fp,pos,SEEK_SET);

fread(&ser_emp,sizeof(emp_rec),1,fp);

printf("\t\t\tDetails of Employee No: %d\n",ser_emp.emp_no);

printf("\tEmployee Name:%s\n",ser_emp.emp_name);

printf("\tEmployee Salary:%lf",ser_emp.emp_sal);

printf("\tEmployee Address:%s\n",ser_emp.emp_add);

printf("\tEmployee Mobile:%s\n",ser_emp.emp_mobile);

}

break;

case 3:

record_update(fp);

break;

case 4:

record_delete(fp,delemp);

break;

case 5:

fseek(fp,0,SEEK_END);

pos=ftell(fp);

fseek(fp,0,SEEK_SET);

while((pos!=ftell(fp))&&(!feof(fp)))

{

fread(&ser_emp,sizeof(emp_rec),1,fp);

if(ser_emp.emp_no!=-1)

{

printf("\t\t\tDetails of Employee No: %d\n",ser_emp.emp_no);

printf("\tEmployee Name:%s\n",ser_emp.emp_name);

printf("\tEmployee Salary:%lf",ser_emp.emp_sal);

printf("\tEmployee Address:%s\n",ser_emp.emp_add);

printf("\tEmployee Mobile:%s\n",ser_emp.emp_mobile);

printf("\n\n"); }

}

break;

case 6:

printf("Exiting...and closing the files\n");

fclose(fp);

fclose(eno);

fclose(delemp);

break;

}

}

}

int main()

{

menu();

return 0;

}