optionGetValue(3) Programmer's Manual optionGetValue(3)

optionGetValue - get a specific value from a hierarcical list

#include <your-opts.h>
cc [...] -o outfile infile.c -lopts [...]

const tOptionValue * optionGetValue(const tOptionValue * pOptValue, char const * valueName);

This routine will find an entry in a nested value option or configurable. If "valueName" is NULL, then the first entry is returned. Otherwise, the first entry with a name that exactly matches the argument will be returned. If there is no matching value, NULL is returned and errno is set to ENOENT. If the provided option value is not a hierarchical value, NULL is also returned and errno is set to EINVAL.
a hierarchcal value
name of value to get

a compound value structure

The returned result is NULL and errno is set:

EINVAL - the pOptValue does not point to a valid hierarchical option value.

ENOENT - no entry matched the given name. @end itemize

The info documentation for the -lopts library.
ao_string_tokenize(3), configFileLoad(3), optionFileLoad(3), optionFindNextValue(3), optionFindValue(3), optionFree(3), optionLoadLine(3), optionMemberList(3), optionNextValue(3), optionOnlyUsage(3), optionPrintVersion(3), optionPrintVersionAndReturn(3), optionProcess(3), optionRestore(3), optionSaveFile(3), optionSaveState(3), optionUnloadNested(3), optionVersion(3), strequate(3), streqvcmp(3), streqvmap(3), strneqvcmp(3), strtransform(3),