BSD 4_3_Net_2 development

[unix-history] / usr / src / sys / tests / benchmarks / bench-4.1 / seqrewrite.c

/*
* Sequential I/O benchmark.
*
* Overwrites existing data in a file.
*/
#include <sys/types.h>
#include <sys/file.h>
#include <sys/stat.h>

char    *malloc();

main(argc, argv)
       char *argv[];
{
       register int i, max;
       char *buf;
       struct stat sb;
       int fd;

       if (argc < 2) {
               printf("usage: %s file\n", argv[0]);
               exit(1);
       }
       fd = open(argv[1], 1);
       if (fd < 0) {
               perror(argv[1]);
               exit(1);
       }
       fstat(fd, &sb);
       buf = malloc(1024);
       max = sb.st_size / 1024;
       printf("%d writes of %d kilobytes\n", max, 1024 / 1024);
       for (i = 0; i < max; i++)
               write(fd, buf, 1024);
}