Terminal size

[cebaa]

Awesome little project!

I assume this is not something that can be solved with this architecture, but just putting it out there in case there's a solution. Since terminal size is returned as (0, 0), it causes issues in some libraries that depend on it, e.g.:

$ cat j.py
import os
import polars

print(os.get_terminal_size())
print(polars.DataFrame(dict(j=['hello world'*50])))

$ python j.py
os.terminal_size(columns=237, lines=73)
shape: (1, 1)
┌─────────────────────────────────┐
│ j                               │
│ ---                             │
│ str                             │
╞═════════════════════════════════╡
│ hello worldhello worldhello wo… │
└─────────────────────────────────┘

$ ./preloaded.py j.py
Existing socket, connected
Python-preloaded fork-server child main, pid 723418
Open new PTY
Send PTY fd to server
Wait for server to be ready
Entering PTY proxy loop
os.terminal_size(columns=0, lines=0)
shape: (1, 1)
┌─────┐
│ j   │
│ --- │
│ str │
╞═════╡
│ hel │
│ lo  │
│ wor │
│ ldh │
│ ell │
│ o   │
│ wor │
│ ldh │
│ ell │
│ o   │
│ wo… │
└─────┘

[albertz]

I'm not sure what polars uses. There is also shutil.get_terminal_size, which additionally also checks the COLUMNS and ROWS env vars if available. Maybe we should also forward these env vars to the server? But if these are not set (usually the case), it falls back to os.get_terminal_size. os.get_terminal_size uses ioctl(fd, TIOCGWINSZ, &w). Maybe we should do TIOCSWINSZ somewhere on the PTY?

[cebaa]

This fork seems to be doing what you're suggesting main...crunchr:python-preloaded:main#diff-c8f775fcee0e436b8616975e26f362c4c62e98830a824cfb5a9f7a71b6470950R174 and it seems to be working fine.

The only thing I'd change is to not hard-code the size, but query the original terminal size and use that. Yeah terminal resizes would be an issue, but they are an issue with hard-coded values as well, so I feel using the original size is a better tradeoff.