Here is a list of all documented files with brief descriptions:

address.h
assert.h
auth.h
auth_address.h
auth_all.h
auth_globus.h
auth_hostname.h
auth_kerberos.h
auth_ticket.h
auth_unix.h
b64.h
batch_file.h
batch_job.h
batch_job_internal.h
batch_task.h
batch_wrapper.h
bitmap.h
bucketing.h
bucketing_exhaust.h
bucketing_greedy.h
bucketing_manager.h
buffer.h
catalog_query.h
catch.h
category.h
category_internal.h
cctools.h
cctools_endian.h
change_process_title.h
chirp_client.h
chirp_matrix.h
chirp_protocol.h
chirp_recursive.h
chirp_reli.h
chirp_stream.h
chirp_types.h
chunk.h
clean_dir.h
compat-at.h
console_login.h
copy_stream.h
copy_tree.h
create_dir.h
daemon.h
datagram.h
debug.h
disk_alloc.h
display_size.h
domain_name.h
domain_name_cache.h
dpopen.h
elfheader.h
envtools.h
fast_popen.h
fd.h
file_cache.h
file_link_recursive.h
full_io.h
get_canonical_path.h
get_line.h
getopt.h
getopt_aux.h
getopt_int.h
gpu_info.h
hash_cache.h
hash_table.h
hdfs_library.h
histogram.h
hmac.h
host_disk_info.h
host_memory_info.h
http_query.h
int_sizes.h
interfaces_address.h
itable.h
jx.h
jx_binary.h
jx_canonicalize.h
jx_eval.h
jx_function.h
jx_getopt.h
jx_match.h
jx_parse.h
jx_pretty_print.h
jx_print.h
jx_sub.h
jx_table.h
link.h
link_auth.h
list.h
load_average.h
macros.h
md5.h
memfdexe.h
mesos_task.h
mkdir_recursive.h
mq.h
nvpair.h
nvpair_jx.h
nvpair_private.h
password_cache.h
path.h
path_disk_size_info.h
pattern.h
ppoll_compat.h
preadwrite.h
process.h
random.h
rmonitor.h
rmonitor_poll.h
rmonitor_poll_internal.h
rmonitor_types.h
rmsummary.h
s3_file_io.h
semaphore.h
set.h
sh_popen.h
sha1.h
shell.h
sigdef.h
sleeptools.h
sort_dir.h
stats.h
string_array.h
string_set.h
stringtools.h
taskvine.h
taskvine_json.h
text_array.h
text_list.h
timer.h
timestamp.h
tlq_config.h
trash.h
twister.h
unlink_recursive.h
uptime.h
url_encode.h
username.h
uuid.h
work_queue.h
xxmalloc.h