`os`

OS thin wrapper - execute a shell command string, read/set environment variables, get and change the current working directory, get the process ID, get command-line arguments, exit the process, and read/write files with type-checked paths. A validated thin layer over host syscalls.

Load with: use os

What this module does

os is a convenience façade over raw __sys_* syscalls and host_run_ctx bindings. Every function validates its argument types and throws a clear eru.bang error on misuse. It mirrors the interface of host but adds stricter type guards and covers the most common OS operations in one import.

Quick example

use os

# Run a shell command
osrun("ls -la")

# Environment
prn(osenv("HOME"))
ossetenv("DEBUG", "1")

# Process
prn(oscwd())
osset("/tmp")
prn(ospid())
prn(osarg())   # ["./myapp", "--flag"]

# File I/O
src = osrd("input.txt")
oswr("output.txt", src)

# Print and exit
osprntl("done")
osext(0)

# Namespace style
prn(os.env("PATH"))

Functions

Process

osrun(cmd) / os.run(cmd)

Executes shell command string cmd via __os_run.

osarg()

Returns the command-line argument list. Checks host context first, then __sys_args.

ospid()

Returns the current process ID.

osext(code)

Exits the process with numeric exit code.

Environment

osenv(key) / os.env(key)

Gets environment variable key. Checks host context first.

ossetenv(key, val) / os.setenv(key, val)

Sets environment variable key to val.

Filesystem

oscwd()

Returns the current working directory.

osset(path)

Changes the current working directory to path.

osrd(path)

Reads a file as text. Errors if path is not a string.

oswr(path, content)

Writes text to a file. Both arguments must be strings.

Output

ostpri(text) / os.tepri(text)

Writes text to stdout without a trailing newline.

osprntl(text) / os.prntl(text)

Writes text to stdout with a trailing newline.

Notes

Requires eru and host_run_ctx.