diff --git a/TurboPFor-Integer-Compression/lib/idxseg.c b/TurboPFor-Integer-Compression/lib/idxseg.c
new file mode 100644
index 0000000..2ee47e3
--- /dev/null
+++ b/TurboPFor-Integer-Compression/lib/idxseg.c
@@ -0,0 +1,133 @@
+/**
+    Copyright (C) powturbo 2013-2023
+    SPDX-License-Identifier: GPL v2 License
+
+    This program is free software; you can redistribute it and/or modify
+    it under the terms of the GNU General Public License as published by
+    the Free Software Foundation; either version 2 of the License, or
+    (at your option) any later version.
+
+    This program is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU General Public License for more details.
+
+    You should have received a copy of the GNU General Public License along
+    with this program; if not, write to the Free Software Foundation, Inc.,
+    51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+
+    - homepage : https://sites.google.com/site/powturbo/
+    - github   : https://github.com/powturbo
+    - twitter  : https://twitter.com/powturbo
+    - email    : powturbo [_AT_] gmail [_DOT_] com
+**/
+//    idxseg.c - Inverted Index - Create partitions from DocId file for prallel query evaluation
+#define _LARGEFILE64_SOURCE 1
+#define _FILE_OFFSET_BITS 64
+#include <stdlib.h>
+#include <string.h>
+#include <stdio.h>
+#ifdef __APPLE__
+#include <sys/malloc.h>
+#else
+#include <malloc.h>
+#endif
+
+#include <getopt.h>
+#include "include_/conf.h"
+
+#ifndef min
+#define min(x,y) (((x)<(y)) ? (x) : (y))
+#define max(x,y) (((x)>(y)) ? (x) : (y))
+#endif
+
+unsigned argtoi(char *s) {
+  char *p; unsigned n = strtol(s, &p, 10),f=1;
+  switch(*p) {
+     case 'k': f = 1000;       break;
+     case 'm': f = 1000000;    break;
+     case 'g': f = 1000000000; break;
+     case 'K': f = 1<<10;      break;
+     case 'M': f = 1<<20;      break;
+     case 'G': f = 1<<30;      break;
+  }
+  return n*f;
+}
+
+void usage() {
+  fprintf(stderr, "\nTurboPFor Copyright (c) 2013-2023 Powturbo  %s\n", __DATE__);
+  fprintf(stderr, "Partitioning\n");
+  fprintf(stderr, "Usage: idxseg -nNs -sPs <docid file> <destination dir>\n");
+  fprintf(stderr, "Ns=total number of documents. Ps=number of partitions\n");
+  fprintf(stderr, " s = modifier s:k,m,g=(1000,1 million,1 billion) s:K,M,G=(1024,1MB,1GB) ex. 64k or 64K\n");
+  fprintf(stderr, "ex. ./idxseg gov2.sorted . -n26m -s8\n");
+  fprintf(stderr, "ex. ./idxseg clueweb09.sorted . -n60m -s8\n\n");
+  fprintf(stderr, "ex. parallel query evaluation\n\n");
+  fprintf(stderr, "./idxqry ~/gov2.sorted.s*.i ~/aol.txt\n\n");
+  exit(-1);
+}
+
+#define SEGMAX 64
+int main(int argc, char *argv[]) { unsigned sb = 8,fno,n=25300000; char *path="";
+  int c, digit_optind = 0, this_option_optind = optind ? optind : 1, option_index = 0;
+  static struct option long_options[] = { {"r",     0, 0, 'r'}, {0,0, 0, 0}  };
+  for(;;) {
+    if((c = getopt_long(argc, argv, "s:n:", long_options, &option_index)) == -1) break;
+    switch(c) {
+      case  0 : printf("Option %s", long_options[option_index].name); if(optarg) printf (" with arg %s", optarg);  printf ("\n"); break;
+      case 's': sb = atoi(optarg); break;
+      case 'n': n  = argtoi(optarg); break;
+      default:  usage();
+    }
+  }
+  if(argc - optind < 2) usage();
+  path = argv[--argc];
+    #ifndef SPOW2
+  sb = (n+sb-1) / sb;
+    #endif
+  for(fno = optind; fno < argc; fno++) {
+    unsigned           snum = 0;
+    unsigned long long inum=0;
+    char               outname[257], *inname = argv[fno];
+    strcpy(outname, path);
+    char *p = strrchr(inname,'/'); if(!p) p = strrchr(inname,'\\'); if(!p) p=inname; strcat(outname, p); strcat(outname,".s");
+
+    FILE *fi = fopen(inname, "rb"); if(!fi) { fprintf(stderr, "open error '%s'", inname); perror(inname); exit(-1); }
+    FILE *fo[SEGMAX] = {0};
+    unsigned as[SEGMAX] = {0}, an[SEGMAX] = {0},s;
+
+    unsigned *in = NULL,*ip, num, numx = 0, tid = 0,didmax=0;
+    while(fread(&num, 1, 4, fi) == 4) {                                     inum+=num;
+      if(num > numx) {
+        numx = num;
+        if(!(in = realloc(in,  num*4+64))) die("malloc err=%u", num);
+      }
+
+      if(fread(in, 4, num, fi) != num) break;                               // read docid list
+      for(ip = in; ip < in+num; ip++) {                                     if(*ip > didmax) didmax=*ip;
+          #ifdef SPOW2
+        s = (*ip) >> sb;
+          #else
+        s = (*ip) / sb;
+          #endif
+        snum = max(snum,s+1); as[s] = as[s]?as[s]:(ip - in); an[s]++;
+      }
+
+      for(s = 0; s < snum; s++) {
+        FILE *f = fo[s];
+        if(!f) {
+          char oname[257]; sprintf(oname, "%s%.2d", outname, s);
+          f = fopen(oname,"wb"); if(!f) { fprintf(stderr, "creat error '%s'", oname); perror(oname); exit(-1); }
+          fo[s] = f;
+          int i; for(i = 0; i < tid; i++) { unsigned z = 0; if(fwrite(&z, 1, 4, f) != 4) die("write error"); printf("#");fflush(stdout); }
+        }
+        unsigned n = an[s];
+        if(fwrite(&n,            1, 4, f) != 4 || (n && fwrite(in+as[s], 4, n, f) != n)) die("write error");
+        as[s] = an[s] = 0;
+      }
+      tid++;
+    }
+    for(s = 0; s < snum; s++) if(fo[s]) fclose(fo[s]); printf("didmax=%u num docid=%llu\n", didmax, inum);
+    free(in);
+  }
+}