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#include <stdio.h> #include <unistd.h> #include <string.h> #include <stdlib.h> #include <sys/wait.h>
int main(void) { FILE *f, *fi, *fp; int p[2], n=0, i, pid, pid2, status, flag = 0, pos = 5, len=0; long int ssn, phone; char nm[80], department[20]; Loop: (^) if ( flag == -1 )int opt; printf("\nPlease make sure that:\nSSN is 9 digits\nHome-Phone is 10 digits\n\n"); printf("Select one option\n1. New Record\n2. Exit\n Enter your choice:"); scanf("%d", &opt);
switch(opt) { case 1: printf("\nSocial Security Number(nine digits number):"); scanf("%ld", &ssn); printf("\nName:"); scanf("%s", nm); printf("\nDepartment:"); scanf("%s", department); printf("\nHome Phone(10 digits number):");
scanf("%ld", &phone); break; case 2: exit(2); }
int name_len = strlen(nm); int dept_len = strlen(department);
pipe(p); /* setting up the pipe / if ((pid = fork()) ==0) / in child / { //printf("\nChild 1 fork successful and the pid for the child is: %d\n", getpid()); close(p[1]); / child closes p[1] */ dup2(p[0], 0); close(p[0]); read(p[0], &ssn, sizeof(ssn)); read(p[0], nm, name_len); read(p[0], &phone, sizeof(phone)); read(p[0], department, dept_len); long int ssn_len_check = ssn, phone_len_check = phone; while(ssn_len_check != 0) { ssn_len_check = ssn_len_check/10; len++; } if(len != 9) {
goto Loop; } else {pos = pos + 9; Loop1: while(!feof(fi)) { c = fgetc(fi); pos++; if(c == '\n') { pos = pos + 6; fseek(fi, pos, SEEK_SET); fgets(sn, sizeof(sn)+2, fi); ssn1 = atoi(sn); if(ssn1 == ssn) { printf("\nThe SSN entered is already registered with us.\n\n"); goto Loop; } pos = pos + 8; } } } fclose(fi); } f=fopen("emps.dat", "a"); fprintf(f ,"SSN:\t%ld \t\tName:\t%s \t\tHome-Phone:\t%ld \n",ssn,nm,phone);
fclose(f); fp=fopen("dept.dat", "a"); fprintf(fp ,"SSN:\t%ld \t\tDepartment: \t %s \n",ssn, department); fclose(fp); _exit(0); /* child terminates */ }
if ((pid2 = fork ()) == 0) /* child two */
{ printf("\nChild 2 fork successful and the pid for the child is: %d\n", getpid()); close(p[0]); dup2(p[1],1); /* 1 becomes a duplicate of p[1] / close(p[1]); write(p[1], &ssn, sizeof(ssn)); write(p[1], nm, strlen(nm)); write(p[1], &phone, sizeof(phone)); write(p[1], department, strlen(department)); } close(p[0]); close(p[1]); / finished writing p[1] */
while (wait(&status)!=pid); /* waiting for pid */ if (status == 0) printf("child finished\n"); else printf("child failed\n"); return(0); }
