This reads a an unsorted index file *.ind and writes a sorted, and converted

/*
This reads a an unsorted index file *.ind and writes a sorted, and converted
*.sor index file
File Names are specialized to the INRSTeX reference book
.. DOS version uses strncmpi()
*/

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

#define NUL ((char)0)
#define BSLASH ((char)0x5c)
#define CR ((char)0x0d)
#define LF ((char)0x0a)
#define MAX 900
#define CS 20
#define SS 510
#define PL 8
/* type def */

typedef struct {
char cmp_str[CS];
char *str;
} ind;

/* the variables */

FILE *outfile; /* out file. */
FILE *infile; /* input file */
char in_buf[512]; /* input buffer */
ind index[MAX];
char work[512];
int j, k, l, cp, in_len ; /* dummy vars */
int mem_over, op;

/* Comparison Function */
int sortfcn(const void *a, const void *b)
{
return (strcmpi(a,b));
}

/*****
* The main function.
input file name is masth.ind output is masth.sor ... for inrstex ref book
*****/
void main()
{printf("\n INRSTeX index massage and sort. \n Input file is 'masth.ind'. \n Output file is 'masth.sor'.\n");
infile = fopen( "masth.ind", "r");
if (infile==0) printf("\n Sorry ... I can't find the index file \n `masth.ind` \n");
else {
outfile = fopen( "masth.sor", "w" );
j=0; while (j<MAX) {k=0; while (k<CS) {index[j].cmp_str[k]=' '; k++;}
j++; index[j].cmp_str[CS-1]=0;
}
mem_over=0;
cp=0;
while ((fgets(in_buf, 510, infile))&&(cp<MAX))
{ in_len=strlen(in_buf);
index[cp].str=malloc(in_len);
if (index[cp].str==0) {mem_over=1;
printf("\n Memory Overflow");
break;
}
strncpy(index[cp].str, in_buf, SS-1);
j=0; k=0;
while ((j<CS-PL-1)&&(in_buf[k]!=LF))
{ if (isalpha(in_buf[k])) {
index[cp].cmp_str[j]=in_buf[k];
j++;
}
k++;
}
if (j==5) {j=0; while (j<5) {index[cp].cmp_str[j]=' '; j++; } }
/* fix for single non-alphabetic commands */
cp++;
}
qsort((void *) index, cp, sizeof(ind), sortfcn);
printf("\n %d index records were read and sorted. \n", cp);
op=0;
while (op<cp)
{
strncpy(work, index[op].str, SS-1);
if (work[0]=='!')
{fputc(BSLASH,outfile);fputc('2',outfile);
k=1; while (work[k]!='!')
{ if ((work[k]=='*')&&(work[k+1]=='/')&&(work[k+2]=='*'))
{fputc(LF,outfile); k++;k++;}
else
{fputc(work[k],outfile);
if (work[k]==BSLASH) fputc('1',outfile);
}
k++;
}

k++; while ((work[k]!=LF)&&(work[k]!=0))
{fputc(work[k],outfile); k++;}
fputc(LF,outfile);
}
op++;
}

fclose(infile); fclose(outfile);
}
}