There is a function that asks the user which text file to open, opens it and then passes the array of structures that was passed into the function along with the file pointer to another function that reads in data from file into the structure. The array structure for testing purposes only has the value char name[25];. I can assign one line at a time from the file to the same structure index all I want but when I try an increment it I get a segmentation fault no matter what approach I've taken.
The structure has been type defined as well.
The code is:
void oSesame(char usrTxt[], int len, FILE * pFile, Country * p)
{
pFile = fopen(usrTxt, "rw");
if(pFile != NULL)
{
readIn(pFile, &p);
}
else
{
printf("Error opening %s , check your spelling and try again.\n", usrTxt);
}
}
void readIn(FILE * pfile, Country ** p)
{
int count = 0;
int i = 0;
for(i = 0; i<3; i++)
{
fgets((*p[i]).cntName, MAX_COUNTRY_LENGTH, pfile);
}
fclose(pfile);
}
The header file:
//Header.h
#define COUNTRY_MAX 10
#define MAX_COUNTRY_LENGTH 25
#define MAX_CAPITAL_LENGTH 25
typedef struct country
{
char cntName[MAX_COUNTRY_LENGTH];
char capName[MAX_CAPITAL_LENGTH];
double population;
}Country;
int ask(char * usrTxt);
void oSesame(char usrTxt[], int len, FILE * pFile, Country * p);
void readIn(FILE * pFile, Country ** p);
The main code:
#include <stdio.h> //for testing within main
#include <string.h> //for testing within main
#include "headers.h"
int main()
{
int len;
FILE * fileP;
char UI[25];
Country c[10];
Country * ptr;
ptr = c;
len = ask(UI);
oSesame(UI, len, fileP, ptr);
return 0;
}
You are passing Country** for some reason and then handling it as *p[index]. This is wrong. You could use (*p)[index] but the correct way is not to take a reference to the Country* in the first place.
The way you're doing it means you have a pointer to pointer to Country. When you index that you are moving to next pointer to pointer, which is not the same as moving to the next pointer. Undefined behaviour happens.
Related
I have currently made this much of the code:
#include <stdio.h>
#include <stdlib.h>
#include <stdbool.h>
#include <ctype.h>
#define STRSIZE 21
struct PInven{
int count;
struct PItem{
char name[STRSIZE];
int amount;
}Pitem;
}Pinven;//this needs to be an output file
int ReadInProduce (){
//read in file and check to see if the file exist or not.
FILE * PinFile = fopen("produce.txt","r");
if (PinFile == NULL){
printf("ERROR: WRONG FILE");
}
else{
printf("I did it!!\n");
}
//assigning the value gotten into the struct variable(but need to maybe change this since it needs to be an output)
fscanf(PinFile,"%d",&Pinven.count);
printf("%d\n", Pinven.count);
int i;
for(i =0; i <Pinven.count; i++){
fscanf(PinFile,"%20s %d",Pinven.Pitem.name, &Pinven.Pitem.amount);
printf("%s %d\n",Pinven.Pitem.name, Pinven.Pitem.amount);
}
//making an array to hold the variables
//FILE * PoutFile = fopen("produce_update.txt","w");
fclose(PinFile);
return 0;
}
From there I want to get the file that is read to the structs to be printed out into an array so that later on I can make a function that will be able to compare to the to it.
Basically a store management system. Where the file of the inventory is read in and compared to the file that is store and return a new value for the amount of produce now either left or gained.
10 //number of items that will be stored in the store
apple 19
banana 31
broccoli 9
...
In general, it's a really bad idea to include header information in the file about the number of entries in the file. You want to be able to do stream processing, and that will be more difficult if you need that meta-data. More importantly, it is important to understand how to write the code so that you don't need it. It's not really that difficult, but for some reason people avoid it. One simple approach is just to grow the array for each entry. This is horribly inefficient, but for the sake of simplicity, here's an example that expects the file not not include that first line:
#include <stdio.h>
#include <stdlib.h>
#include <stdbool.h>
#include <ctype.h>
#include <limits.h>
#define STRSIZE 128
struct PItem{
char name[STRSIZE];
int amount;
};
struct PInven{
int count;
struct PItem *PItem;
};
static void
grow(struct PInven *p)
{
p->PItem = realloc(p->PItem, ++p->count * sizeof *p->PItem);
if( p->PItem == NULL ){
perror("out of memory");
exit(1);
}
}
int
ReadInProduce(struct PInven *P, const char *path)
{
FILE * PinFile = fopen(path, "r");
if( PinFile == NULL ){
perror(path);
exit(1);
}
char fmt[64];
int max_len;
max_len = snprintf(fmt, 0, "%d", INT_MAX);
snprintf(fmt, sizeof fmt, "%%%ds %%%dd", STRSIZE - 1, max_len - 1);
grow(P);
struct PItem *i = P->PItem;
while( fscanf(PinFile, fmt, i->name, &i->amount) == 2 ){
i += 1;
grow(P);
}
P->count -= 1;
fclose(PinFile); /* Should check for error here! */
return P->count;
}
int
main(int argc, char **argv)
{
struct PInven P = {0};
char *input = argc > 1 ? argv[1] : "produce.txt";
ReadInProduce(&P, input);
struct PItem *t = P.PItem;
for( int i = 0; i < P.count; i++, t++ ){
printf("%10d: %s\n", t->amount, t->name);
}
}
As an exercise for the reader, you should add some error handling. At the moment, this code simply stops reading the input file if there is bad input. Also, it would be a useful exercise to do fewer reallocations.
you should change Structure of PInven to it can save a dynamic array of Pitem with a Pitem pointer.
tested :
#include <ctype.h>
#include <stdbool.h>
#include <stdio.h>
#include <stdlib.h>
#define STRSIZE 21
typedef struct {
char name[STRSIZE];
int amount;
} Pitem;
struct PInven {
int count;
Pitem *pitem;
} Pinven; // this needs to be an output file
int main() {
// read in file and check to see if the file exist or not.
FILE *PinFile = fopen("produce.txt", "r");
if (PinFile == NULL) {
printf("ERROR: WRONG FILE");
} else {
printf("I did it!!\n");
}
// assigning the value gotten into the struct variable(but need to maybe
// change this since it needs to be an output)
fscanf(PinFile, "%d", &Pinven.count);
Pinven.pitem = (Pitem *)malloc(sizeof(Pitem) * Pinven.count);
printf("%d\n", Pinven.count);
int i;
for (i = 0; i < Pinven.count; i++) {
fscanf(PinFile, "%20s %d", Pinven.pitem[i].name,
&Pinven.pitem[i].amount);
// printf("%s %d\n",Pinven.pitem[i].name, Pinven.pitem[i].amount);
}
for (i = 0; i < Pinven.count; i++) {
printf("%s %d\n", Pinven.pitem[i].name, Pinven.pitem[i].amount);
}
// making an array to hold the variables
// FILE * PoutFile = fopen("produce_update.txt","w");
fclose(PinFile);
// remember free
free(Pinven.pitem);
return 0;
}
I have written a program which read values from a the file. The data in the file is in following format.
100 Full Name SomeDetails.
234 Full Name SomeDetails
Following is the program which i wrote.
#include <stdio.h>
#include <stdlib.h>
#include<string.h>
#define MAX 10
struct student
{
int rollno;
char name[20];
char course[25];
};
int main()
{
FILE *fptr;
fptr=fopen("records.txt","r");
struct student s[10];
int i=0,tstudent=0;
char che;
char line[100];
//SECTION : 1.1 -> READING NUMBER OF LINES
while(!feof(fptr))
{
che=fgetc(fptr);
if(che=='\n')
{
tstudent++;
}
}
printf("Total Lines in File = %d\n",tstudent);
fclose(fptr);
//SECTION : 1.2 -> READING RECORDS FROM FILE
fptr=fopen("records.txt","r");
char newString[20][20];
int ii,j,ctr;
j=0;
ctr=0;
for(i=0; i<tstudent; i++)
{
fgets(line,100,fptr);
printf("Value of Line %d = %s",i,line);
for(ii=0; ii<=(strlen(line)); ii++)
{
// if tab or NULL found, assign NULL into newString[ctr]
if(line[ii]=='\t'||line[ii]=='\0')
{
newString[ctr][j]='\0';
ctr++; //for next word
j=0; //for next word, init index to 0
}
else
{
newString[ctr][j]=line[ii];
j++;
}
}
}
for(ii=0; ii < ctr; ii++)
{
printf("\n%s",newString[ii]);
}
printf("Value of ctr = %d",ctr);
fclose(fptr);
}
Above code is working fine, BUT all the code is in main function, but i want to make a separate function which can be called from main file and return me every data of file in two dimensional or one dimensional array as return value.
Any help/suggestions would be appreciated.
I tried following CODE as a separate function.. NOT WORKING.
#include <stdio.h>
#include <stdlib.h>
#include<string.h>
char readfile(int tstudent,FILE* filename)
{
//FUNCTION TO READ RECORDS FROM FILE.
FILE *fptr;
int i,k;
char line[100];
char newString[20][20];
int j=0,ctr=0;
fptr=fopen("records.txt","r");
for(i=0; i<tstudent; i++)
{
fgets(line,100,fptr);
printf("Value of Line %d = %s",i,line);
for(k=0; k<=(strlen(line)); k++)
{
// if tab or NULL found, assign NULL into newString[ctr]
if(line[k]=='\t'||line[k]=='\0')
{
newString[ctr][j]='\0';
ctr++; //for next word
j=0; //for next word, init index to 0
}
else
{
newString[ctr][j]=line[k];
j++;
}
}
}
return newString;
}
I defined a new variable char results[] in main function.. and tried to called the function as follows
results[]=readfile(tstudent,fptr)
but when trying to read results.. its showing garbage
char readfile(int tstudent,FILE* filename)
...
char newString[20][20];
...
return newString;
That can't be a good thing, right? You define readFile to return one single character (not a pointer, just one byte) and then return an array instead. We should not be surprised the compiler complained.
If you "fix" that be redefining the return type, you still have a problem because newString is an automatic local variable. The storage (memory) it defines is undefined outside the function.
The easiest way for a function to populate a structure (or array) in C is for the caller to pass it as a function parameter. So you wind up with something more like:
int readfile( FILE* input, char newString[][20], int tstudent )
where newString is defined the same way as you have it, but by the caller, not in readfile. Cf. the stdio functions like fgets; most of them require the caller to define the buffer they read into.
I'll just point out a few more mistakes.
Whenever you call a function -- especially an I/O function -- check for errors. You may want to read tstudent records, but how many are there? If you ask for 5 and find only 1, what then? Your read loop must test for end-of-file, and readfile must return the number of records read, else the caller will never know. Compare with how fread(3) works. Those Unix guys knew a thing or two about how to define a function!
Now your function looks something like this:
int readfile( FILE* input, char newString[][20], int tstudent ) {
char line[100], *s;
int i=0;
for( ; i < tstudent && (s = fgets(line, sizeof(line), input)) != NULL; i++ ) {
/* do stuff with line */
}
/* check for EOF/error if s is NULL, and report */
return i;
}
I want to create a hash table for an exercise I have to send in my University.
The program will open a number of files, break each file's content to <<words>> (tokens) and it will save each <<word>> in a hash table with the frequency of each <<word>>.
In case the word is already in the hash table , the program will increase the word's frequency.
At the end the program will print the words and it's frequencies accordingly.
Also the frequencies should be printed from the highest word frequency to the lowest.
The comparison of the <<words>> will ignore upper and lower case letters.
For example if a file contains : one two three four Two Three Four THREE FOUR FoUr
It should print:
four 4
three 3
two 2
one 1
The professor gave us a template that we should complete but I'm really confused on what to do with the insert_ht() and clear_ht() functions as well as the compare one.
Here is the code :
#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <ctype.h>
#define HTABLE_SIZ 1001
#define MAX_LINE_SIZ 1024
/* Hash Table */
typedef struct node* link;
struct node { char *token; int freq; link next; };
link htable[HTABLE_SIZ] = { NULL }; /* Table of lists (#buckets) */
int size = 0; /* Size (number of elements) of hash table */
unsigned int hash (char *tok );
void insert_ht (char *data);
void clear_ht ( );
void print_ht ( );
void Process(FILE *fp);
int main(int argc, char *argv[])
{
int i;
FILE *fp;
for (i=1; i < argc; i++)
{
fp = fopen(argv[i],"r");
if (NULL == fp)
{
fprintf(stderr,"Problem opening file: %s\n",argv[i]);
continue;
}
Process(fp);
fclose(fp);
}
print_ht();
clear_ht();
return 0;
}
void Process(FILE *fp)
{
const char *seperators = " ?!'\";,.:+-*&%(){}[]<>\\\t\n";
char line[MAX_LINE_SIZ];
char *s;
while((fgets(line,MAX_LINE_SIZ, fp)) != NULL)
{
for (s=strtok(line,seperators); s; s=strtok(NULL,seperators))
insert_ht(s);
}
}
/* Hash Function */
unsigned int hash(char *tok)
{
unsigned int hv = 0;
while (*tok)
hv = (hv << 4) | toupper(*tok++);
return hv % HTABLE_SIZ;
}
void insert_ht(char *token)
{
……………………………………………
}
void clear_ht()
{
……………………………………………
}
int compare(const void *elem1, const void *elem2)
{
……………………………………………
}
void print_ht()
{
int i, j=0;
link l, *vector = (link*) malloc(sizeof(link)*size);
for (i=0; i < HTABLE_SIZ; i++)
for (l=htable[i]; l; l=l->next)
vector[j++] = l;
qsort(vector,size,sizeof(link),compare);
for (i=0; i < size; i++)
printf("%-50s\t%7d\n",vector[i]->token,vector[i]->freq);
free(vector);
}
I'll answer you in a new post because it's hard to be exhaustive in comments.
1. Malloc
Why would I need to use malloc then ? Shouldn't i write directly to the htable? (on the insert_ht() funtion)
You need to use malloc because you declare a char pointer in struct (char *token). The thing is that you never initialize the pointer to anything, and as far you don't know the size of the token, you need to malloc every token. But, as you use strdup(token), you don't need to malloc token because strdup does. So don't forget to free every token in order to avoid memory leaks.
2. Segfault
I can't test you code, but it seems like the following line causes the segmentation fault :
list = htable[hashval]->token
Indeed, you try to access token while htable[hashval] is NULL, and to assign a char * to a link type (list).
You need to loop with this :
for(list = htable[hashval]; list != NULL; list = list->next) { ... }
3. Notes
if (x=1) should be if(x==1).
Don't malloc new_list if you don't need to.
Because new_list if used when htable[hashval] is NULL, new_list->next = htable[hashval]; will set new_list->next to NULL.
You should use the -Wall option in gcc (for warnings) and you may use valgrind to understand your segmentation faults. In this case, use gcc with debug mode (-g).
Double and Final edit : Ι found the solution. Apparently for some reason my compare function was wrong.
I still haven't figured out why but here is the correct one, hopefully someone else will find this post helpful!
int compare(const void *elem1, const void *elem2)
{
return (*(link*)elem2)->freq - (*(link*)elem1)->freq;
}
Edit: deleted old answer . Found the correct way I think but I have another problem right now.
The compare function doesn't work correctly. My printf is fine but it doesnt sort them with the frequiencies. I want them to be sorted from the highest to lowest .
In this example: the file contains -> one two three four Two Three Four THREE FOUR FoUr
And I get:
two 2
one 1
four 4
three 3
While I should be getting :
four 4
three 3
two 2
one 1
Here is the code. Feel free to help!
#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <ctype.h>
#define HTABLE_SIZ 1001
#define MAX_LINE_SIZ 1024
/* Hash Table */
typedef struct node* link;
struct node { char *token; int freq; link next; };
link htable[HTABLE_SIZ] = { NULL }; /* Table of lists (#buckets) */
int size = 0; /* Size (number of elements) of hash table */
unsigned int hash (char *tok );
void insert_ht (char *data);
void clear_ht ( );
void print_ht ( );
void Process(FILE *fp);
int main(int argc, char *argv[])
{
int i;
FILE *fp;
printf("prin tin for \n");
for (i=1; i < argc; i++)
{
printf("prin tin fopen \n");
fp = fopen(argv[i],"r");
if (NULL == fp)
{
fprintf(stderr,"Problem opening file: %s\n",argv[i]);
continue;
}
printf("prin tin process \n");
Process(fp);
fclose(fp);
}
print_ht();
//clear_ht();
return 0;
}
void Process(FILE *fp)
{
const char *seperators = " ?!'\";,.:+-*&%(){}[]<>\\\t\n";
char line[MAX_LINE_SIZ];
char *s;
while((fgets(line,MAX_LINE_SIZ, fp)) != NULL)
{
for (s=strtok(line,seperators); s; s=strtok(NULL,seperators)){
printf("prin tin insert %s \n",s);
insert_ht(s);
}
}
}
/* Hash Function */
unsigned int hash(char *tok)
{
printf("bike stin hash \n");
unsigned int hv = 0;
while (*tok)
hv = (hv << 4) | toupper(*tok++);
printf("VGAINEIIIIIIIIIIIIII %d \n",hv);
return hv % HTABLE_SIZ;
}
void insert_ht(char *token)
{
printf("bike stin insert %s \n",token);
unsigned int hashval = hash(token);
if (htable[hashval]==NULL){
printf("mesa stin prwti if %u %s \n",hashval,token);
//token = strdup(token);
htable[hashval] = malloc(sizeof(token));
htable[hashval]->token = token ;
htable[hashval]->freq = 1;
size++;
}else {
htable[hashval]->freq++;
}
printf("ta evale epitixws \n");
}
int compare(const void *elem1, const void *elem2)
{
const struct node *p1 = elem1;
const struct node *p2 = elem2;
if ( p1->freq < p2->freq)
return -1;
else if (p1->freq > p2->freq)
return 1;
else
return 0;
}
void print_ht()
{
int i, j=0;
link l, *vector = (link*) malloc(sizeof(link)*size);
for (i=0; i < HTABLE_SIZ; i++)
for (l=htable[i]; l; l=l->next)
vector[j++] = l;
qsort(vector,size,sizeof(link),compare);
for (i=0; i < size; i++)
printf("%-50s\t%7d\n",vector[i]->token,vector[i]->freq);
free(vector);
}
Sorry for my bad english.
I think that :
insert(char *token) takes a word of the file and puts into the hash table. In brief, if the word exists in the hash table, you just have to increment its frequencie. Otherwise, you need to create another node and put the frequencie to 1, then ad it to the array. At the end, you will have one entry for each unique word.
compare(const void *elem1, const void *elem2) will be used by qsort. It returns 0 if elem1 = elem2, a negative number if elem1 < elem2 and a number > 0 if elem1 > elem2. By passing compare to qsort, you allow qsort to sort you array according to your own criteria.
clear_ht() may set all the values of the array to NULL, in order to restart another count ?
I'm doing a school assignment and the driver was given to me along with the header file. My job is to complete the functions that read data from a text file and then search it for a name and return the email address. It's a huge exercise in using pointers and structures.
The program reads in a text file of names and email addresses then dynamically creates a structure array using malloc(). The struct Card is built of two char pointers and I find the length of the data using strlen(), malloc() memory for that size and assign the struct to the memory address given.
It all seems to work fine until the end after it has printed the name and email and is about to free() the memory. I get an Aborted (core dump) message every time. Don't know what the issue could be.
I've placed a printf() just before the free() to try and track down where the issue is but it appears to be happening either during the name/email printout or just after it happens because my printf() test point that is one line before the free() is never executed.
I'm assuming the driver program is okay and it has something to do with my functions.
Anyone care to take a stab at it?
//Main
#include <stdio.h>
#include <stdlib.h>
#include "lab9utils.h"
int main(int argc, char * argv[]) {
// Variable declarations.
struct Card * cards;
int size;
int k;
char * email;
// Make sure we have 2 extra command-line paramgers.
if (argc < 3) {
printf("Usage: ./lab9.exe <data_filename> <name_to_lookup>");
return 0;
}
// Get the cards and do the lookup.
cards = getCards(argv[1], &size);
email = lookup(cards, argv[2], size);
// Display the output message ("sorry!" or "name -> email").
if (email == NULL) {
printf("Sorry, that name was not in the list of cards.\n");
} else {
printf("%s -> %s\n", argv[2], email);
}
// Free the memory used by the structures.
k = 0;
printf("Test Point#1");
for (k = 0; k < size; k++) {
free(cards[k].name);
free(cards[k].email);
}
printf("Test Point#2");
free(cards);
return 0;
}
// Header
#ifndef LAB9UTILS_H
#define LAB9UTILS_H
struct Card {
char * name;
char * email;
};
struct Card * getCards(char * filename, int * size);
char * lookup(struct Card * cards, char * name, int size);
#endif
// Functions
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include "lab9utils.h"
struct Card * getCards(char * filename, int * size_return) {
int i,size;
char cTempName[51]={0};
char cTempEmail[51]={0};
size = 0;
// I/O Setup
FILE *fp;
fp = fopen(filename,"r");
// error checking
if(fp == NULL)
{
perror("Error in opening file");
return(NULL);
}
// Input Loop
while(!feof(fp))
{
fscanf(fp,"%s%s",cTempName,cTempEmail);
size++;
}
size=size-1;
fclose(fp);
struct Card * card = (struct Card *)malloc(*size_return * sizeof(struct Card));
fp = fopen( filename ,"r");
// error checking
if(fp == NULL)
{
perror("Error in opening file");
return(NULL);
}
for(i=0;i<size;i++)
{
fscanf(fp,"%s%s",cTempName,cTempEmail);
card[i].name=(char *)malloc((strlen(cTempName)+1));
card[i].email=(char *)malloc((strlen(cTempEmail)+1));
strcpy(card[i].name,cTempName);
strcpy(card[i].email,cTempEmail);
}
fclose(fp);
// loop to confirm data was read
for(i=0;i<size;i++)
{
printf("[ %d ] Name:%s email:%s Total size:%d\n",i,card[i].name,card[i].email,size);
}
*size_return = size;
return card;
}
char * lookup(struct Card * cards, char * name, int size) {
int i;
for(i=0;i<size;i++)
{
if (strcmp(cards[i].name,name)==0)
{
return cards[i].email;
}
}
return NULL;
}
The value of *size_return is garbage, because you are setting it to size only at the end of the function.
Change this:
struct Card * card = (struct Card *)malloc(*size_return * sizeof(struct Card));
To this:
struct Card * card = (struct Card *)malloc(size * sizeof(struct Card));
I have a segmentation fault...i'm not sure what's causing it. Also, when passing the member pname into the function get_names, am I doing this correctly, or is there a better way of doing this?
#include <stdio.h>
#define MAX_NAME 20
#define MAX_PLAYRS 16
typedef struct {
char pname[MAX_NAME];
int runs;
char how_out;
} Team_t;
Team_t player[MAX_PLAYRS];
Team_t *player_ptr[MAX_PLAYRS];
void get_names (int count, char *str);
int main (void) {
int i;
for (i = 0; i < MAX_PLAYRS; i++) {
get_names(i, &(*player[i].pname));
printf("Player: %s\n", player[i].pname);
}
}
void get_names (int count, char *str) {
FILE *inp;
char status;
inp = fopen("teamnames.rtf", "r");
status = fscanf(inp, "%s", str);
if (status == EOF) {
count = MAX_PLAYRS;
}
}
With your code unchanged, I get a segmentation fault if the file can't be opened properly (i.e. it's unreadable due to permissions, or it simply does not exist).
Here's a modified version of you function get_names():
void get_names(int count, char *str)
{
FILE *inp;
inp = fopen("teamnames.rtf", "r");
if (inp == NULL) {
perror("Failed");
return;
}
fgets(str, MAX_NAME, inp);
fclose(inp);
}
This would still read the first name 16 times, but it would tell you why it didn't manage to open the file. To read the next name from the file (rather than repeatedly the first name), open (and close) the file in the main() function instead.
Also, you might as well call get_names() like so:
get_names(i, player[i].pname);
No need to do that &(*...) thing you're doing.
And, finally, I hope that the teamnames.rtf file is not actually an RTF file, but a simple text file with a name on each line.
The problem comes from this line:
get_names(i, &(*player[i].pname));
Understanding pointers and dereferencing is one of the biggest adjustments to learning C if you are switching from another language. You're doing it wrong, and I think you should seek out a tutorial on the subject. Try http://www.cplusplus.com/doc/tutorial/pointers/ as a starting point.
Get a debugger to tell you what is wrong. Compile the code with debugging enabled (see you man page for your compiler) and run something like this:
gdb a.out core
Then you should be able to see which line made the code core dump. You could use idb as well, if you have the intle compiler installed. This is, of course, on *nix. If you are talking windows, use the VS debugger.
In addition do NOT use fscanf as it is unsafe. Use fgets instead.
There are many strange things. First thing is, it seems like the names are in a file, but what you are doing is in every iteration of your for loop, you call get_names which opens the file again, that is goes to the beginning of the file and you read the same name over and over again.
That is if you closed the file. Since you haven't closed the file, the file is already open and you keep reopening it (which could be the cause of your problem)
Another thing is, how can
if (status == EOF) {
count = MAX_PLAYRS;
}
Give you the current count? Regardless of the count of the players in the file, you are just setting it to MAX_PLAYERS.
Another thing is that count is an input to the function that is not a pointer, so setting it does not change the value outside the function (which is what I assumed you wanted).
Here is how I would do it with minimum change to your code:
#include <stdio.h>
#define MAX_NAME 20
#define MAX_PLAYRS 16
typedef struct {
char pname[MAX_NAME];
int runs;
char how_out;
} Team_t;
Team_t player[MAX_PLAYRS];
Team_t *player_ptr[MAX_PLAYRS];
void get_names (int count, char *str, FILE *inp);
int main (void) {
FILE *inp;
int i;
int count;
inp = fopen("teamnames.rtf", "r");
for (i = 0; i < MAX_PLAYRS; i++) {
get_names(&count, player[i].pname, inp);
printf("Player: %s\n", player[i].pname);
}
}
void get_names (int *count, char *str) {
char status;
status = fscanf(inp, "%s", str);
if (status == EOF) {
*count = MAX_PLAYRS;
}
}
Here is how I would do it more concisely:
#include <stdio.h>
#define MAX_NAME 20
#define MAX_PLAYRS 16
typedef struct {
char pname[MAX_NAME];
int runs;
char how_out;
} Team_t;
Team_t player[MAX_PLAYRS];
Team_t *player_ptr[MAX_PLAYRS];
int get_names (Team_t *team);
int main (void) {
get_names(player);
}
int get_names (Team_t *team) {
int i = 0;
FILE *inp;
inp = fopen("teamnames.rtf", "r");
while (i < MAX_PLAYRS && !feof(inp) {
fscanf(inp, "%s", team[i].pname);
printf("Player: %s\n", player[i].pname);
}
}
Note that the problems with fscanf, checking array boundaries etc are not the concern of this solution, but this rather gives you the idea of what to do not a code for you to copy-paste.