Function closefrom 

pub unsafe fn closefrom(lowfd: i32) -> i32

Available on crate feature v2_80 only.

Close every file descriptor equal to or greater than @lowfd.

Typically @lowfd will be 3, to leave standard input, standard output and standard error open.

This is the same as Linux close_range (lowfd, ~0U, 0), but portable to other OSs and to older versions of Linux. Equivalently, it is the same as BSD closefrom (lowfd), but portable, and async-signal-safe on all OSs.

This function is async-signal safe, making it safe to call from a signal handler or a callback::GLib::SpawnChildSetupFunc, as long as @lowfd is non-negative. See [signal(7)](man:signal(7)) and [signal-safety(7)`](man:signal-safety(7)) for more details.

lowfd

Minimum fd to close, which must be non-negative

Returns

0 on success, -1 with errno set on error