[GRASS5] [bug #3514] (grass) r.surf.contour - dozens of warnings

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1

this bug's URL: http://intevation.de/rt/webrt?serial_num=3514
-------------------------------------------------------------------------

Subject: r.surf.contour - dozens of warnings

Platform: GNU/Linux/i386
grass obtained from: CVS
grass binary for platform: Compiled from Sources
GRASS Version: 61 cvs 09.08.05

example:

GRASS 6.1.cvs (caves_utm33):~ > r.surf.contour input=melio_poz_clear_rast output=melio_poz_clear_rast_10_dem2

WARNING: segment_pagein: No such file or directory
WARNING: bseg_put(): could not read segment file at r:64 c:0
WARNING: segment_pagein: No such file or directory
WARNING: bseg_get(): could not read segment file at r:64 c:23
WARNING: segment_pagein: No such file or directory
WARNING: cseg_get(): could not read segment file
WARNING: segment_pagein: No such file or directory
WARNING: cseg_get(): could not read segment file
WARNING: segment_pagein: No such file or directory
WARNING: cseg_get(): could not read segment file
WARNING: segment_pagein: No such file or directory
WARNING: cseg_get(): could not read segment file
WARNING: segment_pagein: No such file or directory
WARNING: cseg_get(): could not read segment file
WARNING: segment_pagein: No such file or directory
WARNING: cseg_get(): could not read segment file
WARNING: segment_pagein: No such file or directory
WARNING: cseg_get(): could not read segment file
WARNING: segment_pagein: No such file or directory
WARNING: cseg_get(): could not read segment file
WARNING: segment_pagein: No such file or directory
WARNING: cseg_get(): could not read segment file
WARNING: segment_pagein: No such file or directory
WARNING: cseg_get(): could not read segment file
WARNING: segment_pagein: No such file or directory
WARNING: cseg_get(): could not read segment file
WARNING: segment_pagein: No such file or directory
WARNING: cseg_get(): could not read segment file
WARNING: segment_pagein: No such file or directory
WARNING: cseg_get(): could not read segment file
WARNING: segment_pagein: No such file or directory
WARNING: cseg_get(): could not read segment file
WARNING: segment_pagein: No such file or directory
WARNING: cseg_get(): could not read segment file
WARNING: segment_pagein: No such file or directory
WARNING: cseg_get(): could not read segment file
WARNING: segment_pagein: No such file or directory
WARNING: cseg_get(): could not read segment file
WARNING: segment_pagein: No such file or directory
WARNING: cseg_get(): could not read segment file
WARNING: segment_pagein: No such file or directory
WARNING: cseg_get(): could not read segment file
WARNING: segment_pagein: No such file or directory
WARNING: cseg_get(): could not read segment file
WARNING: segment_pagein: No such file or directory
WARNING: cseg_get(): could not read segment file
WARNING: segment_pagein: No such file or directory
WARNING: cseg_get(): could not read segment file
WARNING: segment_pagein: No such file or directory
WARNING: cseg_get(): could not read segment file
WARNING: segment_pagein: No such file or directory
WARNING: cseg_get(): could not read segment file
WARNING: segment_pagein: No such file or directory
WARNING: cseg_get(): could not read segment file
WARNING: segment_pagein: No such file or directory
WARNING: cseg_get(): could not read segment file
100%

Although it completes, looks scarry. What is it?

Maciek

-------------------------------------------- Managed by Request Tracker

2

Request Tracker wrote:

this bug's URL: http://intevation.de/rt/webrt?serial_num=3514

Subject: r.surf.contour - dozens of warnings

GRASS 6.1.cvs (caves_utm33):~ > r.surf.contour input=melio_poz_clear_rast output=melio_poz_clear_rast_10_dem2

WARNING: segment_pagein: No such file or directory

Although it completes, looks scarry. What is it?

    if (read (SEG->fd, SEG->scb[cur].buf, SEG->size) != SEG->size)
    {
  G_warning ("segment_pagein: %s\n", strerror(errno));
  return -1;
    }

The warning occurs if read() returns a short count, i.e. if you try to
read beyond the end of the file, or an error.

The actual error message is bogus; read() only sets errno if it
returns a negative result, not if it returns a short count.

--
Glynn Clements <glynn@gclements.plus.com>

3

> this bug's URL: http://intevation.de/rt/webrt?serial_num=3514

> Subject: r.surf.contour - dozens of warnings

> GRASS 6.1.cvs (caves_utm33):~ > r.surf.contour
> input=melio_poz_clear_rast output=melio_poz_clear_rast_10_dem2
>
> WARNING: segment_pagein: No such file or directory

> Although it completes, looks scarry. What is it?

    if (read (SEG->fd, SEG->scb[cur].buf, SEG->size) != SEG->size)
    {
  G_warning ("segment_pagein: %s\n", strerror(errno));
  return -1;
    }

The warning occurs if read() returns a short count, i.e. if you try to
read beyond the end of the file, or an error.

The actual error message is bogus; read() only sets errno if it
returns a negative result, not if it returns a short count.

I've updated the warning in lib/segment/pagein.c, and added a level 2
debug message stating how much was read & how much was asked for.

This shows that the error that pops up in r.cost (at least for me) is a
short count:

G61> r.cost -vk in= out= start_points=`v.to.points -v coastline` \
       percent_memory=50

Null cells excluded from cost evaluation.
Source map is: Integer cell type
20800 rows, 12100 cols.
Creating some temporary files ...
Reading southland_regional_bound ...
D2/2: segment_pagein: read_result=524268 SEG->size=524288
WARNING: segment_pagein: short count during read()
100%
Initializing output
D2/2: segment_pagein: read_result=524268 SEG->size=524288
WARNING: segment_pagein: short count during read()
100%
WARNING: Adapted sites library used for vector points (module should be
         updated to GRASS 6 vector library).
[...]
Finding cost path
   7%
[...?]

Hamish

ps - r.cost can make lots of big temp files. We should catch ^C etc &
remove them. In about 10 minutes I just made 12gig worth....

"top" reports r.cost is using 1948mb ram for a region this big, with
seg=50% and 90k start points. :confused: going into swap makes me sad.
If I try seg=100% then G_malloc() gives an out of memory error right
at the start, which is nice.