typedef struct
{
  char key[4], name[20];
  int mark;
}rec;
int main()
{
   rec recs[10];
   .........
}

memmove   Copies a block of n bytes from src to dest.

 Syntax:
   void *memmove(void *dest, const void *src, size_t n);

 Prototype in:
 mem.h   string.h

 Remarks:
memmove copies a block of n bytes from src to dest.

Even when the source and destination blocks overlap, bytes in the
overlapping locations are copied correctly.

 Return Value:
memmove returns dest.

 Portability:
memmove is available on UNIX System V systems and is compatible
with ANSI C.

 Example:
#include <string.h> 
#include <stdio.h>

 int main(void)
 {
   char *dest = "abcdefghijklmnopqrstuvwxyz0123456789";
   char *src = "******************************";
   printf("destination prior to memmove: %s\n", dest);
   memmove(dest, src, 26);
   printf("destination after memmove:    %s\n", dest);
   return 0;
 }

#include <stdio.h>
#include <string.h>
#include <stdlib.h>

typedef struct
{
	char key[4], Name[21];
	int Mark;
}rec;
void merge(rec * rm, rec * r1, rec * r2, int n1, int n2);
void printRecs(rec * r, int n);
void parseF(char * filename, rec * r, int *n);

int main(void)
{
	int i, n1=0, n2=0;

	rec recs1[10], recs2[10], recs[20];

	char s[27];
	
    	parseF("bin1", recs1, &n1);
        parseF("bin2", recs2, &n2);
	merge(recs, recs1, recs2, n1, n2);
	printRecs(recs, n1+n2);
		
	return 0;
}   
void parseF(char* filename, rec *r, int *n)
{
	FILE *f;
	char *buffer;
	unsigned long fileLen;
	int i, ri, part, ci;

	f = fopen(filename, "rb");
	if ( f == NULL )
	{
		printf("Cannot open record file %s", filename);   
		exit(1);
	}
	fseek(f, 0, SEEK_END);
	fileLen = ftell(f);
	fseek(f, 0, SEEK_SET);
	
	buffer = (char*)malloc(fileLen+1);
	if (!buffer)
	{
		printf("Cannot allocate memory");
		fclose(f);
		exit(1);
	}
	fread(buffer, fileLen, 1, f);
	//r = (rec*)malloc(sizeof(rec)*fileLen/27);
	i  = 0;
	ri = 0; // record count
	ci = 0;; // character count;
	part = 0;
	while(i<fileLen)
	{
		if(buffer[i]=='\0') {continue;}
		if (i%27==0)
		{
			ci=0;
			part = 0;
			ri++;
		}
		if (i%27==3)
		{
			ci=0;
			part = 1;
		}
		if (i%27==23)
		{
			ci=0;
			part = 2;
		}
		if (part == 0)
		{
			printf("%c\n", buffer[i]);
			r[ri].key[ci++] = buffer[i];
		} else if (part == 1)
		{
			printf("%c\n", buffer[i]);
			r[ri].Name[ci++] = buffer[i];
		} else if (part == 2)
		{
			// ??????
		}
		i++;
	}
	fclose(f);
}
void merge(rec * rm, rec * r1, rec * r2, int n1, int n2)
{
	int i1=0, i2=0, i=0;
	while (i1<n1 && i2<n2)
	{
		if (r1[i1].Mark < r2[i2].Mark)
		{
			strcpy(rm[i].key, r1[i1].key);
			strcpy(rm[i].Name, r1[i1].Name);
			rm[i].Mark = r1[i1].Mark;
			i1++;
		}
		else if (r1[i1].Mark > r2[i2].Mark)
		{
			strcpy(rm[i].key, r2[i2].key);
			strcpy(rm[i].Name, r2[i2].Name);
			rm[i].Mark = r2[i2].Mark;
			i2++;
		}
		else
		{
			if (strcmp(r1[i1].Name, r2[i2].Name)<1)
			{
				strcpy(rm[i].key, r1[i1].key);
				strcpy(rm[i].Name, r1[i1].Name);
				rm[i].Mark = r1[i1].Mark;
				i1++;
			}
			else
			{
				strcpy(rm[i].key, r2[i2].key);
				strcpy(rm[i].Name, r2[i2].Name);
				rm[i].Mark = r2[i2].Mark;
				i2++;
			}
		}
		i++;

	}
	while (i1<n1){ rm[i].Mark = r1[i1].Mark; i1++; i++;}
	while (i2<n2){ rm[i].Mark = r2[i2].Mark; i2++; i++;}

}
void printRecs(rec * r, int n)
{
	int i;
	for (i=0;i<n ;i++ )
	{
		printf("%3s  %20s %4d\n", r[i].key, r[i].Name, r[i].Mark);
	}
}

   k = 0;
   do   {    
      i = fscanf(innew, "%64s %U", folders[k].nfield, &folders[k].pfield);     
      k++;   
    }while (i > 0);

AAAJohn Doe\0abcdefghijk1BBBJack Doe\0abcdefghijk2CCCBenn Doe\0abcdefghijk3