Comparing char-array in a struct with user input char-array - c

I am writing a code to search for a specific student in a file, and calculate it's average. everything works except for one thing. When I input the student's name in a char variable, to search for him in the file, the compiler does not get it is equal to a char in the struct of the file...
#include <stdio.h>
#include <stdlib.h>
#define nl printf("\n")
#define N 100
struct student {
char id[N][N];
int vote[10][10];
};
int main()
{
struct student stud;
FILE *filer;
int i=0, j=0, k=0, n_stud=0;
char checker[1], who[N];
float avg[10], mark=0.0, count=0.0;
printf("Introduce student id: ");
scanf("%14s", &who);
printf("Searching for student %s...\n", who);
nl;
filer=fopen("students.dat", "r");
if(filer==NULL) {
printf("Can't open file...\n");
}
for(i=0; fscanf(filer, "%s", &stud.id[i])!=NULL && fscanf(filer, "%c", &checker)!=EOF; ++i) {
for(j=0; fscanf(filer, " %d", &stud.vote[i][j])!=-1; ++j ) {
if(stud.vote[i][j]!=-1) {
mark=mark+stud.vote[i][j];
count++;
} else {
for(k=j; k<10; k++) {
stud.vote[i][k]=0;
}
break;
}
}
n_stud++;
avg[i]=mark/count;
mark=0.0; count=0.0;
}
for(i=0; i<n_stud; ++i){
if (who == stud.id[i]) { //HERE IS THE PROBLEM!!!
printf("Student %s's average is: %.2f", stud.id, avg[i]);
}
}
nl;
fclose(filer);
return EXIT_SUCCESS;
}
File
s11111 30 28 18 -1
sa44er44 23 18 30 18 29 18 29 -1
s33333 30 30 -1
22222idx 18 -1

You cannot compare C-"strings" (which in fact are just char-arrays) using the ==-operator:
if(who==stud.id[i]){
Use the strcmp() function instead:
if (strcmp(who, stud.id[i]) == 0) {
Unrelated, but still important: You want to make sure to not let the user overflow who.
You can do this by telling scanf() the size of who like this:
scanf("%14s", who); /* Tell it one less to have a spare char
to store the '0'-terminator. */
Although scanf(() typically expects an address as argument, you won't pass the address of who, but just who, because an array (which `who^ is) decays to the address of its 1st element., when being passed to a function.

Related

For loop doesn`t work when add [^\n] to a scanf_s

This program should ask you to add member (people) to a struct and print them on a file but after the first for loop just stop working and jump over the name part. I just found that thing that allow you to add space to a string, tried it but no success...
I tried to remove it and it work without any problem so the [^\n] make something go wrong.
What is wrong ?
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
struct Staff {
char Surname[100];
char Name[100];
int age;
char spec[100];
int id;
} person;
void write();
void leggi();
void trova();
int main() {
write();
}
void write() {
int i = 0;
int n = 1;
int r;
FILE *fp;
fopen_s(&fp, "index.txt", "w+");
if (fp == NULL) {
printf("Failed to open file\n");
exit(1);
}
fprintf(fp, "%d\n", i);
for (i = 0; i < n; i++) {
printf("Surame:\n");
scanf_s("%[^\n]s", person.Surname, 100);
fprintf(fp, "%s\t\t", person.Surname);
//loop just get over the name part
printf("Name:\n"); //after the first loop
scanf_s("%s", person.Name, 100);
fprintf(fp, "%s\t", person.Name);
printf("Age:\n");
scanf_s("%d", &person.age);
fprintf(fp, "%d\t", person.age);
printf("Specialization\n");
scanf_s("%s", person.spec, 100);
fprintf(fp, "%s\n", person.spec);
printf("Want to enter another? 1=yes 0=no...\n");
scanf_s("%d", &r);
if (r == 1)
n = n + 1;
}
rewind(fp);
fprintf(fp, "%d\n", i);
fclose(fp);
}
There are multiple problems in your code:
you use the so called secure functions fopen_s, scanf_s etc, but you do not check the return values to detect invalid input. You should instead use standard functions, pass the appropriate arguments and check the return values.
using scanf_s is actually non portable: the scanf_s function defined in Annex K of the C Standard requires the length argument after the pointer to have size_t type, whereas the function with the same name in the Microsoft library uses type UINT, which has a different representation on 64-bit versions of their Windows OS. A classical case of the Embrace, enhance and extinguish strategy. In Standard C, one should write: scanf_s("%s", person.Name, (size_t)100) or better:
scanf_s("%s", person.Name, sizeof person.Name)
there is no need to open the output file for update with "w+", just use "w".
you rewind the stream pointer back to the beginning of file and overwrite the number of entries at the start of the file. This works as long as you have less than 10 entries, but beyond that, the number has more digits so some characters in the file will be corrupted. You could use a format with padding such as "%6d\n" which would allow for up to 1 million records without risks.
"%[^\n]s" is not a correct scanf format: you should just write "%[^\n]" or better " %99[^\n]" to skip initial white space and limit the input to 99 characters.
Here is a modified version:
#ifdef _MSC_VER
#define _CRT_SECURE_NO_WARNINGS
#endif
#include <errno.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
struct Staff {
char Surname[100];
char Name[100];
int age;
char spec[100];
int id;
};
void write(void);
void leggi(void);
void trova(void);
int main() {
write();
}
int flush_input(void) {
int c;
while ((c = getchar()) != EOF && c != '\n')
continue;
return c;
}
void write(void) {
int n = 0;
int r;
FILE *fp = fopen("index.txt", "w");
if (fp == NULL) {
fprintf("Failed to open file index.txt: %s\n",
strerror(errno));
exit(1);
}
fprintf(fp, "%6d\n", n);
for (;;) {
struct Staff person = { 0 };
printf("Surname:\n");
if (scanf(" %99[^\n]", person.Surname) != 1)
break;
flush_input();
fprintf(fp, "%s\t\t", person.Surname);
//loop just get over the name part
printf("Name:\n"); //after the first loop
scanf(" %99[^\n]", person.Name);
flush_input();
fprintf(fp, "%s\t", person.Name);
printf("Age:\n");
scanf("%d", &person.age);
flush_input();
fprintf(fp, "%d\t", person.age);
printf("Specialization\n");
scanf(" %99[^\n]", person.spec, 100);
flush_input();
fprintf(fp, "%s\n", person.spec);
n++;
printf("Want to enter another? 1=yes 0=no...\n");
if (scanf("%d", &r) != 1 || r != 1) {
flush_input();
break;
}
flush_input();
}
rewind(fp);
// update the entry count on 6 characters
fprintf(fp, "%6d\n", n);
fclose(fp);
}
Change the call of scanf below for entering strings by inserting a space in the beginning of the format string. For example instead of this call
scanf_s("%[^\n]s", person.Surname, 100);
(where the letter s must be removed from the format string) write
scanf_s(" %[^\n]", person.Surname, ( rsize_t )100);
^^^^^^^^
This allows to skip leading white space characters in the input buffer.
Pay attention to that changing the condition or the for loop the was as you are doing
for (i = 0; i < n; i++) {
//...
if (r == 1)
n = n + 1;
}
makes the code unclear. Instead of the for loop you could use do-while loop.

how to check variable validity and how to send array of structure to function?

I'm working in library system, I've a lot of things going on:(. In addBook function I'm trying to add book information into Array of structure. First I don't know how to set a statement to check all the validity of title, author, isbn and others. I tried to write a statement but it wont work so I removed it! and didn't call the functions since I don't know how to make them work! secondly I want to send the book information to a file so I can store them inside the file and sort alphabetically. whenever I try to send the array and check the txt file it print the address please help :( I'm trying to keep it simple as possible as I can
#include <stdio.h>
#include <stdlib.h>
#define MAX_ISBN 11
#define MIN_ISBN 9
#define MAX_YEAR 2021
#define MIN_YEAR 1500
#define MAX_DAY 31
#define MIN_DAY 1
#define MAX_MONTH 12
#define MIN_MONTH 1
#define MIN_ISBN 9
#define MAX_Title 80
#define MAX_Author 80
struct Book{
int ISBN[MAX_ISBN], Edition[500], Year[MAX_YEAR],DD[MAX_DAY], MM[MAX_MONTH];
char Title[MAX_Title];
char Author[MAX_Author];
};
/*Check_Title function will check user input if it's a valid title or not! */
int Check_Title(char *Title){
int valid_Title = 1;
int len = 0;
int i= 0;
len = strlen(Title);
for(i =0; i <len ; i++)
{
if( Title[i] == "##$%^&*()}{[ ]")
return 0;;
}
return 1;
}
/*Check_Author function will check user input if it's a valid Author name or not! */
int Check_Author(char *Author){
int valid_Name = 1;
int len = 0;
int i= 0;
len = strlen(Author);
for(i =0; i <len ; i++)
{
if( !(isalpha(Author[i])) && (Author[i] != ' '))
{
valid_Name = 0;
break;
}
}
return valid_Name;
}
int Check_Date(int *DD, int *MM,int *YYYY){
if(DD[MAX_DAY] > MAX_DAY || DD[MIN_DAY]< MIN_DAY)
return 0;
if(MM[MAX_MONTH] >31 || MM[MIN_DAY]<1)
return 0;
if(YYYY[MAX_YEAR]>MAX_YEAR || YYYY[MIN_YEAR]<MIN_YEAR)
return 0;
return 1; //if statement true return 1
}
int Check_ISBN(int *ISBN){
if(ISBN[MAX_ISBN] > MAX_ISBN || ISBN[MIN_ISBN] < MIN_ISBN);
return 0;
return 1; //if ISBN VALID
}
// This function is used to check file existence, every time if it's called
//the following functions is user choice to either add a book, delete, view, and view by year -> Switch cases
void addBook(){
system("cls"); //clearing black screen
int Title_Validity = 0, Name_Validity = 0, ISBN_Validity, Date_Validity = 0,n;
struct Book *insert = NULL;
FILE* ptr = fopen("stored.txt","w");
if (ptr == NULL){
printf("Error opening the file! \n");
exit(1);}
////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
printf("\n\t\t ========================================================================");
printf("\n\t\t ADD NEW BOOK ");
printf("\n\t\t ========================================================================");
printf("\n\n\t\t\tENTER YOUR DETAILS BELOW:");
printf("\n\t\t\t---------------------------------------------------------------------------\n");
////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
printf("\t\tHow many Books would you like to insert? ");
scanf("%d", &n);
for(int i = 0; i<n; i++){
insert = (struct Book*)calloc(n,sizeof(struct Book));
//Inputing Title & Check Title validity
//do{
printf("\n\t\t\tBook Title : ");
fflush(stdin);
fgets(insert[i].Title, MAX_Title, stdin);
/*Title_Validity = Check_Title(&insert[MAX_Title].Title);
if(Title_Validity){
printf("\n\t\t *_*_*_*_*_*_*_*_*_*_*_*_*_*_*_*_*_*_*_*_*_*_*_*_*_*_*_*_*_*_*_*_*__*_*_*_*_*__*_*_*_");
printf("\t\t\t\t\t\t \t\t Invalid Input ! please try again! \n\t\t\t and make sure to not use any digits or special characters! \n ");
printf("\n\t\t *_*_*_*_*_*_*_*_*_*_*_*_*_*_*_*_*_*_*_*_*_*_*_*_*_*_*_*_*_*_*_*_*__*_*_*_*_*__*_*_*_*_");
}
}while(Title_Validity);*/
//Inputing Author
printf("\n\t\t\tBook Author : ");
fflush(stdin);
fgets(insert[i].Author, MAX_Author, stdin);
//Inputing ISBN
//do{
printf("\n\t\t\tBook ISBN : ");
scanf("%d", &insert[i].ISBN);
// fflush(stdin);
//fgets(insert[i].ISBN, MAX_ISBN, stdin);
/* ISBN_Validity = Check_ISBN(&insert[MAX_ISBN].ISBN);
if(ISBN_Validity == 0){
printf("\n\t\t *_*_*_*_*_*_*_*_*_*_*_*_*_*_*_*_*_*_*_*_*_*_*_*_*_*_*_*_*_*_*_*_*__*_*_*_*_*__*_*_*_");
printf("\t\t\t\t\t\t \t\t Invalid Input ! please try again! \n\t\t\t and make sure to not to not accedes the range 9~11! \n ");
printf("\n\t\t *_*_*_*_*_*_*_*_*_*_*_*_*_*_*_*_*_*_*_*_*_*_*_*_*_*_*_*_*_*_*_*_*__*_*_*_*_*__*_*_*_*_");
}
}while(ISBN_Validity!=0);*/
//Inputing Edition
printf("\n\t\t\tBook Edition (only digits acceptable) : ");
scanf("%d", &insert[i].Edition);
//Inputing Date
printf("\n\t\t\tBook Date [DD MM YYYY] : ");
scanf("%d%d%d", &insert[i].DD,&insert[i].MM,&insert[i].Year);
printf("\n\t\t ========================================================================");
printf("\n\t\t The book %s has been added to the library.", insert[i].Title );
printf("\n\t\t ========================================================================");
}
//
Sort_Save(n,&insert[x].Title,&insert[x].Author,&insert[x].ISBN,&insert[x].Edition,&insert[x].DD,&insert[x].MM,&insert[x].Year);
return;
}
void Sort_Save(int n,char Title[MAX_Title],char Author[MAX_Author], int ISBN[MAX_ISBN], int Edition[], int day[MAX_DAY], int month[MAX_MONTH], int year[MAX_YEAR]){
int i;
struct Book *st;
FILE* fptr = fopen("sorted.txt", "w");
if(fptr == NULL){
printf("Error opening file! \n");
exit(1);
}
for(i=0; i<n; i++){
fprintf(fptr,"%s %s %d %d %d %d %d",st[i].Title,st[i].Author,st[i],st[i].ISBN,st[i].Edition,st[i].DD,st[i].MM,st[i].Year);
fprintf(fptr,"\n");
}
printf("\n");
fclose(fptr);
}
Since you're asking the users how much books they want to add, you have to allocate the block of memory only once, best right after (before the loop) and certainly not again and again in the loop, where it gets initialized with '0' (zero, that's what calloc does).
And opening a file with the mode "w" truncates that file to zero length, i don't think that this is what you want. And why do you open it, when you do not access it, neither for reading nor for writing?
After scanning, you call the Sort_Save function with a bunch of useless parameters (where does the variable 'x' come from?). You should declare the function like this:
int sortSave(struct Book *books, size_t size)
and pass the allocated block (insert) with the specified size (n).
If you want to sort your library, then you should open the existing database for read first ("r"), then read all the stored values into an array, append the new data to that array, call 'qsort' (see man qsort), specify your compare function (where you specify by which parameter your library should be sorted), close the file, open it again in write mode ("w") and finally write all your (sorted) data into that file.
Do not to forget to flush and close the file, nor to free the allocated blocks of memory.
Edit:
As a hint, seperate code from design. First make sure your code works as expected, then add all the fancy stuff, best as a seperate function.

How to add strings and integers to an array then print to a text file

Goodday, when I get to entering the first name of the student, the program immediately crashes. Also I'm not exactly sure how to add the names and the ID into an array to print to the text file. May I have some assistance please?
struct records{
int id;
char fname[15];
char lname[15];
};
struct records student;
int max=1000;
int i;
srand( time(NULL) ); //random numbers generated
ATND= fopen("Student Record.txt","a");
if(ATND== NULL){
printf("ERROR!");
exit(1);
}
for(i=0; i<100; i++){
printf("Enter student\'s first name: ");
scanf("%s", student.fname[i]);
printf("\n\n");
printf("Enter student\'s last name: ");
scanf("%s", student.lname[i]);
/*randomnumber*/student.id[i]=rand() %max + 39048543;
fprintf(ATND,"%s %s %d", student.fname[i], student.lname[i], student.id[i]);
}
fclose(ATND);
Code only provides data space for 1 record whereas it appears to need 1000 records. Number of other issues. Suspect after 10 hours, OP has worked a number of them
//Definition - good
struct records {
int id;
char fname[15]; // IMO 15 is too limiting for first and last
char lname[15];
};
// Only 1 student, need many more
// struct records student;
#define STUDENT_N 1000
struct records student[STUDENT_N];
void read_records(void) {
// avoid magic numbers
// int max = 1000;
int max = STUDENT_N;
int i;
srand(time(NULL)); //random numbers generated
// ATND not declared
FILE *ATND;
ATND = fopen("Student Record.txt", "a");
if (ATND == NULL) {
printf("ERROR!");
exit(1);
}
char buf[100];
// avoid magic numbers
// for (i = 0; i < 100; i++) {
for (i = 0; i < STUDENT_N; i++) {
printf("Enter student\'s first name: ");
// don't use scanf()
// scanf("%s", student.fname[i]);
if (fgets(buf, sizeof buf, stdin) == NULL) break;
if (sscanf(buf, "%14s", student[i].fname) != 1) break;
printf("\n\n");
printf("Enter student\'s last name: ");
// Add flush to insure buffered prompts that do not end in \n are sent
fflush(stdout);
// scanf("%s", student.lname[i]);
if (fgets(buf, sizeof buf, stdin) == NULL) break;
if (sscanf(buf, "%14s", student[i].lname) != 1) break;
// /*randomnumber*/student.id[i] = rand() % max + 39048543;
/*randomnumber*/student[i].id = rand() % max + 39048543;
// Do not index the name, index the structure
// fprintf(ATND, "%s %s %d", student.fname[i], student.lname[i], student.id[i]);
fprintf(ATND, "%s %s %d", student[i].fname, student[i].lname, student[i].id);
}
fclose(ATND);
}
Assuming student.fname is a char array of sufficient size
scanf("%s", student.fname[i]);
should be
scanf("%s", student.fname);
You need to pass a pointer to the beginning of the array, NOT the value of the chars, one by one. scanf will enter the entire name in one call.

C parsing fgets() char array into multiple variables with sscanf using structures

In this program it compiles but i get segmentation fault, sscanf(str, "%d %s %s %d %f", &pos, z[pos-1].city, z[pos-1].state, &z[pos-1].population, &z[pos-1].growth); its because this line z[pos-1].city, z[pos-1].state, doesnt have & but when i add that i get warning: format â%sâ expects type âchar *â, but argument 4 has type âchar (*)[200]â.
i'm sure there is another way of doing this, i need to use structure, read in file store info into an array of a structure then displaying the array. the printf works just storing the city and state into char array.
I commented the area where i tried to initialize to array and had an incompatable type with the char array value all three: a, 'a', "a".
#include <stdio.h>
#include <string.h>
#include <stdlib.h>
typedef struct{
int rank;
char city[200];
char state[50];
int population;
float growth;
}city_t;
void read_data(city_t *z)
{
FILE *inp;
inp = fopen("cities.dat", "r");
char str[256];
int pos = 0;
if(inp==NULL)
{
printf("The input file does not exist\n");
}
else
{
/*reads and test until eof*/
while(1)
{
/*if EOF break while loop*/
if(feof(inp))
{break;}
else
{
/*read in a number into testNum*/
//fscanf(inp, "%d", &testNum);
fgets(str,sizeof(str),inp);
sscanf(str, "%d %s %s %d %f", &pos, z[pos-1].city, z[pos-1].state, &z[pos-1].population, &z[pos-1].growth);
z[pos-1].rank = pos;
}
}
}
fclose(inp);
}
void print_data(city_t *z, int size)
{
int i;
printf("rank\tcity\t\tstate\tpopulation\t\tgrowth\n");
for(i=0;i<size;i++)
{
printf("%d\t%s\t\t%s\t\%d\t\t%f\n", z[i].rank, z[i].city, z[i].state, z[i].population, z[i].growth);
}
}
int main()
{
int i;
city_t cities[10];
/*for(i;i<10;i++)
{
cities[i].rank = 0;
cities[i].city = "a";
cities[i].state = "a";
cities[i].population = 0;
cities[i].growth = 0.00;
}*/
read_data(&cities[0]);
print_data(&cities[0], 10);
return(0);
}
{
dat file
1 New_York NY 8143197 9.4
2 Los_Angeles CA 3844829 6.0
3 Chicago IL 2842518 4.0
4 Houston TX 2016582 19.8
5 Philadelphia PA 1463281 -4.3
6 Phoenix AZ 1461575 34.3
7 San_Antonio TX 1256509 22.3
8 San_Diego CA 1255540 10.2
9 Dallas TX 1213825 18.0
10 San_Jose CA 912332 14.4
}
In read_data, you scan into z[pos-1].... where pos starts at 0. So you will be writing beyond (before) the extend of the array.
Just do a global replace of pos-1 with pos and also increment pos; you can also use fscanf, so your reading can be:
for (int pos=0; !feof(inp); ++pos)
{
fscanf(inp, "%d %s %s %d %f",
&z[pos].rank,
z[pos].city,
z[pos].state,
&z[pos].population,
&z[pos].growth);
}

Why can't I input a filename for opening in c?

I have been attempting to debug this program with my limited knowledge, and have compared it with other programs in which i've used the same methods to retrieve a filename for opening. However, it seems that for some odd reason the program does not recieve user input for filename, sometimes getting caught in some sort of an elusive loop.
I have used both:
scanf("%s\n", filename);
and:
gets(filename);
(i know gets is "dangerous" but this is a program that is not going to be distributed, it is an assignment in a college level class)
here is the main() function and the getssn() function (which does get user input successfully):
#include <stdio.h>
#include <stdlib.h>
#include <ctype.h>
#include <string.h>
#define MAXS 19
#define MAXR 999
//structure defining a given client
typedef struct person {
unsigned int ssn, age, height, weight, income;
char name[MAXS+1], job[MAXS+1], religion[MAXS+1], major[MAXS+1], minor[MAXS+1], gender;
}PERSON;
//get and check for ssn validity
int getssn(){
int num;
printf("\nSSN: ");
scanf("%d", &num);
if(num<=99999999 || num>999999999){
printf("\nPlease input a valid SSN.\n");
return 0;
}
else
return num;
}
//read the specified file and check for the input ssn
int readfile(FILE *fptr, PERSON **rptr, int *count){
int v=0, i, j;
char n2[MAXS+1], b[2]=" ";
for(i=0; i<MAXR; i++){
j=i;
//read the file in chunks
if(fscanf(fptr, "%c\n%d\n%19s %19s\n%d\n%19s\n%d\n%19s\n%19s\n%d\n%d\n%19s\n\n",
&rptr[j]->gender, &rptr[j]->ssn, rptr[j]->name, n2, &rptr[j]->age,
rptr[j]->job, &rptr[j]->income, rptr[j]->major, rptr[j]->minor,
&rptr[j]->height, &rptr[j]->weight, rptr[j]->religion)==EOF)
i=MAXR;
//make first and last name one element
strcat(rptr[j]->name, b);
strcat(rptr[j]->name, n2);
//if we find a match, tell main the id
if(rptr[MAXR]->ssn==rptr[j]->ssn)
v=j;
}
//count how many clients we have
*count=j;
return v;
}
//commpare age and income
int cmpai(PERSON rec1, PERSON rec2){
int a=0, inc=0;
if(rec1.age<=(rec2.age+10) && rec1.age>=(rec2.age-10))
a=1;
if(rec1.income<=(rec2.income+10000) && rec1.income>=(rec2.income-10000))
inc=1;
if(a==1 && inc==1)
return 1;
else
return 0;
}
//compare hobbies
int cmph(PERSON rec1, PERSON rec2){
if(strcmp(rec1.major,rec2.major)==0 && strcmp(rec1.minor, rec2.minor)==0)
return 1;
else
return 0;
}
//compare weight, height, and religion
int cmpwhr(PERSON rec1, PERSON rec2){
int w=0, h=0, r=0;
double n1, n2;
n1=rec1.height;
n2=rec2.height;
if(n1<=(n2*1.1) && n1>=(n2*0.9))
h=1;
n1=rec1.weight;
n2=rec2.weight;
if(n1<=(n2*1.1) && n1>=(n2*0.9))
w=1;
if(strcmp(rec1.religion, rec2.religion)==0)
r=1;
if(r==1 && h==1 && w==1)
return 1;
else
return 0;
}
//sort the ids in ascending order by ssn for proper output
void sort(int *A, int count){
int i, j, temp;
for(i=0; i<count; i++)
for(j=0; j<count; j++)
if(A[i+1]<A[i]){
temp=A[i];
A[i]=A[i+1];
A[i+1]=temp;
}
}
//display the possible matches in ascending ssn order
void display(int matches[], PERSON rec[], int count){
int i;
for(i=0; i<count; i++){
if(matches[i]==rec[i].ssn)
printf("%s\n", rec[i].name);
}
}
int main(){
int valid=-1, i, counter=0, *c=&counter, id[MAXR-1], totalmatches;
char filename[MAXS];
FILE *fp;
PERSON record[MAXR+1], *rp[MAXR+1];
//get a ssn from the user
do{
record[MAXR].ssn=getssn();
}while(record[MAXR].ssn==0);
//get a filename
printf("Name of file of records: ");
scanf("%s", filename);
printf("%s", filename);
//open the file, if possible
if((fp=fopen(filename, "r"))==NULL)
perror(filename);
else{
printf("test");
for(i=0; i<=MAXR; i++){
rp[i]=&record[i];
id[i]=0;
}
//read the file, find the matching ssn
valid=readfile(fp, rp, c);
//check if the ssn is in the file, if not tell the user
if(valid<0){
printf("\nSSN %d is not found in file %s.\n", record[MAXR].ssn, filename);
return EXIT_FAILURE;
}
else {
//check for matches and count how many we have
for(i=0; i<counter; i++){
if(i!=valid)
if(record[valid].gender!= record[i].gender)
if(cmpai(record[valid], record[i])==1 || cmph(record[valid], record[i])==1 || cmpwhr(record[valid], record[i])==1){
id[i]=record[i].ssn;
totalmatches+=1;
}
}
//if we have matches sort them and display them, otherwise tell the user he has no match in this group
if(totalmatches>0){
sort(id, counter);
display(id, record, counter);
}
else
printf("\nNo matches.\n");
fclose(fp);
return EXIT_SUCCESS;
}
}
}
This is the current input(single quotes)/output:
run
[Switching to process 6956]
Running…
SSN: '111223333'
Name of file of records: 'clients.txt'
clients.txttest
Debugger stopped.
Program exited with status value:0.
You should your getssn() function. You need to put in a return statement.
int getssn(){
int num;
printf("\nSSN: ");
scanf("%d", &num);
return num; // You MUST put this in.
}
This will improve this code:
do{
record[MAXR].ssn=getssn();
}while(record[MAXR].ssn==0);
If you forget the return, then getssn() might return 0 forever.
You should also tell us what exact output you are seeing. You should copy all the output into your question also.
Never use any of the scanf family of functions; they don't give you nearly enough control over what happens on invalid input, and scanf("%s") is just as dangerous as gets.
But this is probably not your immediate problem. That's much more likely to be a case of trying to open a file by partial pathname when it's not in the current working directory. Try typing in the full pathname (/home/kabir/filename, C:\users\kabir\filename, sort of thing). Also, changing
printf("\nCould not open file\n");
to
perror(filename);
will give you more information when things go wrong.
It should be
scanf("%s", filename)
i.e. remove the \n
Unrelated, but you seem to have forgotten return num at the end of getssn().
Looking at your current code (8:10 pm Dublin/London time), you should use this instead:
//get a filename
printf("Name of file of records: ");
//scanf("%s", filename);
printf("scanned file: <%s>\n", filename);
//open the file, if possible
if((fp=fopen(filename, "r"))==NULL)
perror(filename);
else{
printf("test\n");
...

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