Nyx provides POSIX process builtins: getpid, getcwd, chdir, isatty, stat. These are the building blocks for command-line tools and shells.
68-process-control.nxSource →
// Process control — pid, working directory, environment // Control de procesos — pid, directorio de trabajo, entorno fn main() -> int { // Get current process ID let pid: int = getpid() print("my pid: " + int_to_string(pid)) // Get current working directory let cwd: String = getcwd() print("cwd: " + cwd) // Check if stdout is a terminal let is_tty: bool = isatty(1) if is_tty { print("stdout is a terminal") } else { print("stdout is not a terminal (piped)") } // File stat let info: Array = stat("/tmp") let is_dir: int = info[3] if is_dir == 1 { print("/tmp is a directory") } // Change directory and back let original: String = getcwd() chdir("/tmp") print("changed to: " + getcwd()) chdir(original) print("back to: " + getcwd()) return 0 }
Illustrative outputstdout
my pid: 1501659 cwd: /tmp/demo stdout is not a terminal (piped) /tmp is a directory changed to: /tmp back to: /tmp/demo
How it works
getpid() returns the current process ID. getcwd() returns the current working directory as a string. chdir(path) changes the working directory.
isatty(fd) checks whether a file descriptor refers to a terminal. File descriptor 0 is stdin, 1 is stdout, 2 is stderr. This is useful for deciding whether to emit color codes or interactive prompts.
stat(path) returns metadata about a file or directory as [size, mode, mtime, is_dir, is_regular]. The is_dir flag (index 3) is 1 for directories, 0 otherwise. These primitives are what a shell built in Nyx uses for its built-in commands.