From 1b04047a875e8f3da78417c1a7f232e12490436d Mon Sep 17 00:00:00 2001 From: Heinrich Schuchardt Date: Sun, 29 Jul 2018 11:08:14 +0200 Subject: [PATCH] README: U_BOOT_ENV_CALLBACK functions Describe the interface of environment variable callback functions. Signed-off-by: Heinrich Schuchardt --- README | 11 +++++++++++ 1 file changed, 11 insertions(+) diff --git a/README b/README index aee0f73..a91af2a 100644 --- a/README +++ b/README @@ -3943,6 +3943,17 @@ If CONFIG_REGEX is defined, the variable_name above is evaluated as a regular expression. This allows multiple variables to be connected to the same callback without explicitly listing them all out. +The signature of the callback functions is: + + int callback(const char *name, const char *value, enum env_op op, int flags) + +* name - changed environment variable +* value - new value of the environment variable +* op - operation (create, overwrite, or delete) +* flags - attributes of the environment variable change, see flags H_* in + include/search.h + +The return value is 0 if the variable change is accepted and 1 otherwise. Command Line Parsing: =====================