gfal_testrw.c

This exemple show how to open, write a file and read it after ex : use case with SRM plugin : ./gfal_testrw srm://grid05.lal.in2p3.fr:8446/dpm/lal.in2p3.fr/home/dteam/test_yoda

#include <fcntl.h>
#include <stdio.h>
#include <gfal_api.h>
#include <stdlib.h>
#define BLKLEN 65536

main(int argc, char **argv)
{
   int fd;
   int i;
   char ibuf[BLKLEN];
   char obuf[BLKLEN];
   int rc;

   // gfal_set_verbose(GFAL_VERBOSE_TRACE | GFAL_VERBOSE_VERBOSE);      // switch Gfal in verbose mode
   if (argc != 2) {
           fprintf (stderr, "usage: %s filename\n", argv[0]);
           exit (1);
   }

   for (i = 0; i < BLKLEN; i++)
           obuf[i] = i;

   printf ("creating file %s\n", argv[1]);
   if ((fd = gfal_open (argv[1], O_WRONLY|O_CREAT, 0644)) < 0) {
                gfal_posix_check_error();
                exit (1);
   }
   
        printf ("open successful, fd = %d\n", fd);

        if ((rc = gfal_write (fd, obuf, BLKLEN)) != BLKLEN) {
                gfal_posix_check_error();
                (void) gfal_close (fd);
                exit (1);
        }
        printf ("write successful\n");

        if ((rc = gfal_close (fd)) < 0) {
                gfal_posix_check_error();
                exit (1);
        }
        printf ("close successful\n");


        printf ("reading back %s\n", argv[1]);
        if ((fd = gfal_open (argv[1], O_RDONLY, 0)) < 0) {
                gfal_posix_check_error();
                exit (1);
        }
        printf ("open successful, fd = %d\n", fd);

        if ((rc = gfal_read (fd, ibuf, BLKLEN)) != BLKLEN) {
                        gfal_posix_check_error();
                        (void) gfal_close (fd);
                        exit (1);
           }
           printf ("read successful\n");

           if ((rc = gfal_close (fd)) < 0) {
                        gfal_posix_check_error();
                        exit (1);
           }
           printf ("close successful\n");

           for (i = 0; i < BLKLEN; i++) {
                   if (ibuf[i] != obuf[i]) {
                                fprintf (stderr, "compare failed at offset %d\n", i);
                                exit (1);
                   }
           }
           printf ("compare successful\n");
           exit (0);
}

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