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   Uniform File Access Library

1. Architecture
   

   The Architecture of UFAL is depicted in the following figure.
   
   
   
   

2. Pre-requisites
   

   Supported Platform: GNU/Linux is supported as a development and production platform.

3. Installation
   

   Download UFAL rpm package from here. After install the rpm, you can use UFAL tools and library. 
   

4. How to use
   

   (1) Configuration
   Please  modify the enviornment variable "UFAL_NETFS"  and "UFAL_DEBUG" in /etc/profile.d/ufal.sh or ufal.csh "UFAL_NETFS" defines which directory should be considered as network file system. UFAL_DEBUG defines the debug options, and 0 shows no debugging infomation is printed into terminal. For example,
   export UFAL_DEBUG=0
   export UFAL_NETFS="/besfs /afs"
   Of course, you can override the setting through the configuration file in your own home directory, eg, .bash_profile.  
   (1) Command Line
   One uniform file copy tool (ufcp) is embeded in UFAL, the syntax is:
   ufcp [-vVh] src_file dest_file
   -v: verbose mode, will shows the instant speed of copying
   -V: shows the version
   h: show the help.
   For example,
   ufcp -v root://cdev02.ihep.ac.cn//besfs/chyd/f1 /tmp/f1
   (2) Programming with UFAL library
   A program reading one file and print it to output:
    
   /*
    * Copyright (C) 2008-2010 by IHEP/CC
    * All rights reserved
    * unicp.c v0.1 2009-04-06 16:06:22
    * Written by Yaodong Cheng, Computing Center, IHEP
    * Contact: Yaodong.cheng@ihep.ac.cn
    */
   #include <stdio.h>
   #include <string.h>
   #include <stdlib.h>
   #include <unistd.h>
   #include <fcntl.h>
   #include <dirent.h>
   #include <errno.h>
   #include <sys/time.h>
   #include <pthread.h>
   #include <pwd.h>
   #include "ufal_api.h"
   
   int main(int argc, char *argv[])
   {
           int fd;
           int c;
           char *fn;
           char buf[RECSIZE+1];
           if (argc < 2){
                   printf("usage: %s filename\n", argv[0]);
                   return(-1);
           }
   #ifdef _USEXRD
           xrd_init(OP_META);
   #endif
           fn = argv[1];
           fd = uf_open64(fn, O_RDONLY, 0644);
           if (fd < 0){
                   //printf("%s\n", strerror(errno));
                   perror("uf_open");
                   return (-1);
           }
           bzero(buf, sizeof(buf));
           while ((c = uf_read(fd, buf, sizeof(buf))) > 0){
                   fprintf(stdout, "%s", buf);
                   bzero(buf, sizeof(buf));
           }
           if (uf_close(fd) < 0){
                   perror("uf_close");
                   exit (-1);
           }
           exit (0);
   }
   Then link it with UFAL library:
   

   gcc -o ufcat ufcat.c -I/opt/ufal/include -lufal -L/opt/ufal/lib -I/usr/include/shift -D_LARGEFILE64_SOURCE