Hello,
I have a installed grass-6.0.2 on a linux FC4 machine. Configuration of
this machine is as 1.4Ghz processor, 512MB RAM, 70GB (SCSI HDD) and FC4 is
the only OS on the machine, also the swap space provided to the OS is of
1.5 GB.
The problem that I am facing is I am unable to use >=2gb ESRI Arc/Info
ASCII Grid Raster dataset. It seem to keep reporting an error that "File
too large" .
After exploring the net for the same I came to know that while
configuration the --enable-64bit=yes for enabling the Grass to read >2GB
dataset and make and make install.
Even after doing so the grass still is not able to accept dataset >=2gb.
If anyone know how to make r.in.arc read file >=2gb.
Regards
Nagaraj
Unfortunately not all GRASS modules have large file support. It is
possible, that r.in.arc is also in this list.
Q. to dev's: Is there any short how-to how check large file support in
GRASS module and how to enable it (which variables and functions
should be checked etc.)?
Maris.
On 4/19/06, Nagaraj Thanushkodi <Nagaraj.Thanushkodi@rmsi.com> wrote:
Hello,
I have a installed grass-6.0.2 on a linux FC4 machine. Configuration of
this machine is as 1.4Ghz processor, 512MB RAM, 70GB (SCSI HDD) and FC4 is
the only OS on the machine, also the swap space provided to the OS is of
1.5 GB.
The problem that I am facing is I am unable to use >=2gb ESRI Arc/Info
ASCII Grid Raster dataset. It seem to keep reporting an error that "File
too large" .
After exploring the net for the same I came to know that while
configuration the --enable-64bit=yes for enabling the Grass to read >2GB
dataset and make and make install.
Even after doing so the grass still is not able to accept dataset >=2gb.
If anyone know how to make r.in.arc read file >=2gb.
Regards
Nagaraj
Mâris Nartie-B¹s wrote:e-A
Q. to dev's: Is there any short how-to how check large file support in
GRASS module and how to enable it (which variables and functions
should be checked etc.)?
If the --enable-largefile configure option is used, the header
<grass/config.h> will define some macros which cause off_t to be
defined as a 64-bit type and the I/O functions declared in <unistd.h>
to be the 64-bit versions (open64 etc).
If a module only does sequential file access (open, read/write,
close), including <grass/config.h> before any other headers will be
sufficient (note that <grass/gis.h> includes <grass/config.h>).
OTOH, if the module uses lseek(), you need to modify the code so that
offsets are computed and stored as off_t rather than int or long.
Apart from changing variables and fields to have type off_t, you also
need to ensure that calculations such as:
offset = row * cols * bytes;
are promoted to off_t, e.g.:
offset = (off_t) row * cols * bytes;
If a file uses the ANSI fseek/ftell functions, the situation is more
complex. Those functions are defined to use the C long type for
offsets. C99 has fseeko/ftello, which use off_t, but those aren't
available on all platforms, so you would need to add configure tests
and only use them if they are available.
--
Glynn Clements <glynn@gclements.plus.com>