GetTagArg

Finds a TagArg in list and returns its ta_Arg field.

Synopsis

TagData GetTagArg (const TagArg *tagList, uint32 tag,TagData defaultValue)

Description

This function calls FindTagArg() to locate the specified tag. If it is found, it returns the ta_Arg value from the found TagArg. Otherwise, it returns the default value supplied. This is handy when resolving a tag list that has optional tags that have suitable default values.

Arguments

tagList: The list of tags to scan. Can be NULL.

tag: The tag ID to look for.

defaultValue: Default value to use when specified tag isn't found in tagList.

Return Value

ta_Arg value from found TagArg or defaultValue.

Implementation

Convenience call implemented in clib.lib V24.

Examples

void dosomething (const TagArg *tags)
{
    uint32 amplitude = (uint32)GetTagData (tags, MY_TAG_AMPLITUDE, (TagData)0x7fff);
    .
    .
    .
}

Caveats

It's a good idea to always use casts for the default value and result. Don't assume anything about the type definition of TagData other than that it is a 32-bit value.

Associated Files

tags.h: ANSI C Prototype

clib.lib: ARM Link Library