[#CRYPTO_THREAD_run_once]
= CRYPTO_THREAD_run_once
:mrdocs:

Run `init` exactly once across threads using a CRYPTO_ONCE control.

== Synopsis

Declared in `<openssl/crypto.h>`

[source,cpp,subs="verbatim,replacements,macros,-callouts"]
----
int
CRYPTO_THREAD_run_once(
    xref:CRYPTO_ONCE.adoc[CRYPTO_ONCE]* once,
    void(* init)());
----

== Return Value

1 on success, or 0 on failure.

== Parameters

[cols="1,4"]
|===
| Name| Description
| *once*
| Once‐control variable (initialize with CRYPTO_ONCE_STATIC_INIT).
| *init*
| Function invoked at most once process‐wide for `once.`
|===


[.small]#Created with https://www.mrdocs.com[MrDocs]#