err = __syscall_chown (file, owner, group);
err = INLINE_SYSCALL (chown, 3, __ptrvalue (file), owner, group);
__chown (const char *file, uid_t owner, gid_t group){   int err;   int old_errno;   char link[PATH_MAX+2];   char path[2*PATH_MAX+4];   int loopct;   int filelen;   static int libc_old_chown = 0 /* -1=old linux, 1=new linux, 0=unknown */;   if (libc_old_chown == 1)     return __syscall_chown (file, owner, group);   old_errno = errno;#ifdef __NR_lchown   if (libc_old_chown == 0)     {       err = __syscall_chown (file, owner, group);       if (err != -1 || errno != ENOSYS)	 {	   libc_old_chown = 1;	   return err;	 }       libc_old_chown = -1;     }#endif   err = __readlink (file, link, PATH_MAX+1);   if (err == -1)     {       errno = old_errno;       return __lchown(file, owner, group);     }   filelen = strlen (file) + 1;   if (filelen > sizeof(path))     {       errno = ENAMETOOLONG;       return -1;     }   memcpy (path, file, filelen);   /* 'The system has an arbitrary limit...'  In practise, we'll hit      ENAMETOOLONG before this, usually.  */   for (loopct = 0; loopct < 128; loopct++)   {     int linklen;     if (err >= PATH_MAX+1)       {	 errno = ENAMETOOLONG;	 return -1;       }      link[err] = 0;  /* Null-terminate string, just-in-case.  */      linklen = strlen (link) + 1;      if (link[0] == '/')	memcpy (path, link, linklen);      else	{	  filelen = strlen (path);	  while (filelen > 1 && path[filelen-1] == '/')	    filelen--;	  while (filelen > 0 && path[filelen-1] != '/')	    filelen--;	  if (filelen + linklen > sizeof(path))	    {	      errno = ENAMETOOLONG;	      return -1;	    }	  memcpy (path+filelen, link, linklen);	}      err = __readlink(path, link, PATH_MAX+1);      if (err == -1)      {	errno = old_errno;	return __lchown(path, owner, group);      }   }   errno = ELOOP;   return -1;}