hostname(3d) - 3d

NAME

hostname - Get the environment's hostname with gethostname(2)

SYNOPSIS

import hostname : hostname, hostnamez;

immutable string hostname;

immutable char* hostnamez;

DESCRIPTION

The hostname module has a shared static initializer that calls gethostname(2) once, into a static buffer, and then initializes string and immutable char*‌ typed variables with the contents of that buffer, without copying.

A failure of gethostname(2) is treated as an unrecoverable error, guarded by an assert().

EXAMPLE

#! /usr/bin/env dub
/+ dub.sdl:
    dependency "hostname" version="~>0.1.2"
+/

void main() {
    import std.stdio : writeln;
    import hostname : hostname;

    writeln("hostname: ", hostname);
}

BETTERC EXAMPLE

#! /usr/bin/env dub
/+ dub.sdl:
    dependency "hostname" version="~>0.1.2"
    buildOptions "betterC"
+/

extern(C) void main() {
    import core.stdc.stdio : printf;
    import hostname : hostnamez;

    printf("hostname: %s\n", hostnamez);
}

SEE ALSO

gethostname(2), Sys::Hostname(3pm)

BUGS

Due to issue #22031 (crt_constructor functions can't initialize immutable/const variables) the hostname and hostnamez variables aren't immutable when the library is compiled with -betterC.

FUTURE DIRECTIONS

This module hard-codes the value of HOST_NAME_MAX. When importC is available, that should be used instead.

Perhaps the statically initialized hostnames should be in an optional submodule, separate from a module that just wraps gethostname(2)? The current implementation is what I've wanted 100% of the time, but in other environments hostnames can be subject to change.

COLOPHON

This page is part of the 0.1.2 release of the hostname DUB package. This package can be found at https://code.dlang.org/packages/hostname/. Issues should be submitted to https://github.com/jrfondren/hostname-d/issues.

D - June 7, 2021