Infinite loop

Iam getting infinite loop while executing the code:-

#include<stdio.h>
#include<stdlib.h>
#include<ctype.h>
#include<string.h>
#define MaxStudents 100
#define MaxNameLength 30
#define MaxNameBuffer MaxNameLength+1
typedef struct{
int age;
char gender;
char name[MaxNameBuffer];
} Student;
int main(){ //begin main
Student pupil[MaxStudents];
char aname[MaxNameBuffer];
void getString(FILE *, char[]);
int getData(FILE *, Student[]);
int search(char[], Student[], int);
void sort(Student[], int);
void printStudent(Student);
void getString(FILE *, char[]);
FILE * in = fopen("input.txt", "r");
if(in == NULL){
printf("Error opening input file.\n");
exit(1);

}
int numStudents = getData(in, pupil);
if(numStudents==0){
printf("No data supplied for students\n");
exit(1);
}
for(int h=0;h<numStudents;h++){
printStudent(pupil[h]);
}
printf("\n");
getString(in, aname);
while(strcmp(aname,"END") != 0)
{
 int ans = search(aname, pupil, numStudents);
if(ans==-1)
        printf("%s not found \n", aname);
else
printf("%s found at location %d\n",aname,ans);

}// while end
getString(in, aname);
sort(pupil, numStudents);
printf("\n");
for (int h=0;h<MaxStudents;h++){
printStudent(pupil[h]);
}
}//main end
void printStudent(Student t){
printf("Name :%s, Age:%d, Gender:%c\n",t.name,t.age,t.gender);
} //end printStudent
int getData(FILE *in, Student list[])
{
char temp[MaxNameBuffer];
void getString(FILE *, char[]);
char readChar(FILE *);
int n=0;
getString(in,temp);
while(n<MaxStudents && strcmp(temp,"END")!=0){
strcpy(list[n].name,temp);
fscanf(in,"%d",&list[n].age);
list[n].gender=readChar(in);
n++;
getString(in,temp);
}
return n;
}

int search(char key[], Student list[], int n){
for(int h=0;h<n;h++){
if(strcmp(key,list[h].name)==0 ) return h;
return -1;
}
}//end Search
void sort(Student list[], int n){
Student temp;
int k;
for(int h=1;h<n;h++){
temp=list[h];
k=h-1;
while(k>=0 && strcmp(temp.name, list[k].name) < 0){
list[k+1]=list[k];
k-=1;
}
list[k+1]=temp;
}//end for
}//end sort
void getString(FILE * in, char str[]){
char ch,delim;
int n=0;
str[0]='\0';
while(isspace(ch=getc(in)));
if(ch==EOF)
        return;
delim=ch;
while(((ch=getc(in)) != delim) && (ch!=EOF))
        str[n++]=ch;
str[n]='\0';
}//end getString
char readChar(FILE * in){
char ch;
while(isspace(ch=getc(in)));
return ch;
}