Inappropriate ioctl for device when

[NikosAlexandris]

I am trying to execute a python script, like :

``` bash exec="true" result="ansi" source="material-block"
some-python-script \
    --start-time '2010-01-27' \
    --end-time '2010-01-28' \
    --quiet \
    --uniplot
```

where one of the outputs, of it, is a uniplot. The script fails to complete, however, before plotting when it tries to fetch the size of the terminal using Python's os.get_terminal_size() and the error is :

│   295 │   if uniplot:                                                                            │
│   296 │   │   print(f'[reverse]Uniplot[/reverse]')                                               │
│   297 │   │   import os                                                                          │
│ ❱ 298 │   │   terminal_columns, _ = os.get_terminal_size() # we don't need lines!                │
│   299 │   │   terminal_length = int(terminal_columns * terminal_width_fraction)                  │
│   300 │   │   from functools import partial                                                      │
│   301 │   │   from uniplot import plot as default_plot                                           │
..
OSError: [Errno 25] Inappropriate ioctl for device

Can I work-around this [Errno 25] Inappropriate ioctl for device ?

[pawamoy]

Hey, thanks for the report. I was able to reproduce the described error:

```bash exec="true" result="ansi" source="material-block"
python <<EOF
import os
print(os.get_terminal_size())
EOF
```

I observed that it is not specific to Markdown Exec:

% python -c 'import os; print(os.get_terminal_size())' | cat
Traceback (most recent call last):
  File "<string>", line 1, in <module>
OSError: [Errno 25] Inappropriate ioctl for device

Instead of os.get_terminal_size(), you can use shutil.get_terminal_size(), which won't fail:

% python -c 'import shutil; print(shutil.get_terminal_size())' | cat            
os.terminal_size(columns=80, lines=24)

I found this by reading the docstring of the os method:

>>> import os
>>> help(os.get_terminal_size)
Help on built-in function get_terminal_size in module posix:

get_terminal_size(...)
    Return the size of the terminal window as (columns, lines).
    
    The optional argument fd (default standard output) specifies
    which file descriptor should be queried.
    
    If the file descriptor is not connected to a terminal, an OSError
    is thrown.
    
    This function will only be defined if an implementation is
    available for this system.
    
    shutil.get_terminal_size is the high-level function which should
    normally be used, os.get_terminal_size is the low-level implementation.

You can see how shutil achieves this with python -c 'import inspect, shutil; print(inspect.getsource(shutil.get_terminal_size))'.

Or you could catch the error and use default values:

try:
    terminal_columns, _ = os.get_terminal_size()
except OSError:
    terminal_columns = 80