# `QuakeServer.Autocvars`
[🔗](https://github.com/jaman/quake_server/blob/v0.1.0/lib/quake_server/autocvars.ex#L1)

A program's `autocvar_<name>` globals kept equal to console variable `<name>`, and a
server's info keys kept equal to its `:serverinfo` and `:userinfo` variables, as FTE
keeps them (`PR_AutoCvar`, `Cvar_SetCore`).

    server = QuakeServer.Autocvars.sync(server)

The host is a `QuakeServer.Server` (a server, a client program's world or a menu)
holding a `QuakeServer.Cvars` table in `cvars`. The first `sync/1` of a program
attaches it, as FTE does when a program loads: each `autocvar_` global (a float,
integer, vector or string; not a float named like a vector's `_x`, `_y` or `_z`)
names a variable, made when there is none with the global's own value as its default
(`%g` for a float, `%i` for an integer, `%g %g %g` for a vector), and is given the
variable's value; a variable programs may not read (`:nounsafeexpand`) is left out.
On a server (one with player slots) every `:serverinfo` variable with a value becomes
a server info key and every `:userinfo` one an info key of each player slot; one
without a value removes its key.

Every later `sync/1` whose table changed since the last brings every attached global
and every info key up to date. A float global takes the variable's `value`, an integer
its `ival`, a string its text (empty text the null string) and a vector the first
three words of the text read as numbers. `QuakeServer.Server.exec_opts/1` runs
`sync/1` before every call into a program, so a change made by any process holding
the table reaches each program before it next runs.

# `format_g`

```elixir
@spec format_g(number()) :: String.t()
```

A float as C's `%g` writes it: six significant digits, trailing zeros dropped.

# `sync`

```elixir
@spec sync(map()) :: map()
```

Attach the host's program, or bring it up to date with its table; see the module documentation.

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*Consult [api-reference.md](api-reference.md) for complete listing*