Wireshark · Wireshark-dev: Re: [Wireshark-dev] [Wireshark-commits] rev 51169: / /trunk/epan/: app_mem_usage.c

[Dirk Jagdmann <doj@xxxxxxxxx>]

> If not, would an lseek() followed by a read() do just as well?

No. lseek() and read() modify the file position/offset. pread() however does 
*not* modify it. So to emulate pread() you would need something like:

ssize_t my_pread(int fd, void *buf, size_t count, off_t offset)
{
  const off_t old_offset = lseek(fd, 0, SEEK_CUR); // missing error handling
  lseek(fd, offset, SEEK_SET); // missing error handling
  const ssize_t ret = read(fd, buf, count);
  lseek(fd, old_offset, SEEK_SET); // missing error handling
  return ret;
}

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---> Dirk Jagdmann
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