/test.mp3:
$ fq
exitcode: 2
stderr:
Usage: fq [OPTIONS] [--] [EXPR] [FILE...]
$ fq -h
fq - jq for binary
Tool, language and decoders for exploring binary data.
For more information see https://github.com/wader/fq

Usage: fq [OPTIONS] [--] [EXPR] [FILE...]
--compact,-c               Compact output
--decode,-d=NAME           Decode format (probe)
--file,-f=PATH             Read EXPR from file
--formats                  Show supported formats
--help,-h                  Show help
--include-path,-L=PATH     Include search path
--join-output,-j           No newline between outputs
--null-input,-n            Null input (can still use input/0 and inputs/0)
--null-output,-0           Null byte between outputs
--option,-o=KEY=VALUE,...  Set option, eg: color=true
                             addrbase=16
                             bitsformat=snippet
                             bytecolors=0-0xff=brightwhite,0=brightblack,32-126:9-13=white
                             color=false
                             colors=array=white,dumpaddr=yellow,dumpheader=yellow+underline,error=brightred,false=yellow,index=white,null=brightblack,number=cyan,object=white,objectkey=brightblue,string=green,true=yellow,value=white
                             decodeprogress=false
                             depth=0
                             displaybytes=16
                             linebytes=16
                             raw=false
                             sizebase=10
                             unicode=false
                             verbose=false
--raw-output,-r            Raw string output (without quotes)
--repl,-i                  Interactive REPL
--slurp,-s                 Read (slurp) all inputs into an array
--version,-v               Show version (dev)
$ fq -i
null> ^D
$ fq -i . /test.mp3
mp3> ^D
$ fq -n
exitcode: 2
stderr:
Usage: fq [OPTIONS] [--] [EXPR] [FILE...]
$ fq -ni
null> ^D
$ fq -n 123
123
$ fq -ni 123
number> ^D
$ fq -n "[1,2,3]"
[
  1,
  2,
  3
]
$ fq -nc "[1,2,3]"
[1,2,3]
$ fq --formats
Name:              Description:
aac_frame          Advanced Audio Coding frame
adts               Audio Data Transport Stream
adts_frame         Audio Data Transport Stream frame
apev2              APEv2 metadata tag
av1_ccr            AV1 Codec Configuration Record
av1_frame          AV1 frame
av1_obu            AV1 Open Bitstream Unit
avc_au             H.264/AVC Access Unit
avc_dcr            H.264/AVC Decoder Configuration Record
avc_nalu           H.264/AVC Network Access Layer Unit
avc_pps            H.264/AVC Picture Parameter Set
avc_sei            H.264/AVC Supplemental Enhancement Information
avc_sps            H.264/AVC Sequence Parameter Set
bzip2              bzip2 compression
dns                DNS packet
elf                Executable and Linkable Format
exif               Exchangeable Image File Format
flac               Free Lossless Audio Codec file
flac_frame         FLAC frame
flac_metadatablock FLAC metadatablock
flac_picture       FLAC metadatablock picture
gif                Graphics Interchange Format
gzip               gzip compression
hevc_au            H.265/HEVC Access Unit
hevc_dcr           H.265/HEVC Decoder Configuration Record
hevc_nalu          H.265/HEVC Network Access Layer Unit
icc_profile        International Color Consortium profile
id3v1              ID3v1 metadata
id3v11             ID3v1.1 metadata
id3v2              ID3v2 metadata
jpeg               Joint Photographic Experts Group file
json               JSON
matroska           Matroska file
mp3                MP3 file
mp3_frame          MPEG audio layer 3 frame
mp4                MPEG-4 file and similar
mpeg_asc           MPEG-4 Audio Specific Config
mpeg_es            MPEG Elementary Stream
mpeg_pes           MPEG Packetized elementary stream
mpeg_pes_packet    MPEG Packetized elementary stream packet
mpeg_spu           Sub Picture Unit (DVD subtitle)
mpeg_ts            MPEG Transport Stream
ogg                OGG file
ogg_page           OGG page
opus_packet        Opus packet
png                Portable Network Graphics file
protobuf           Protobuf
protobuf_widevine  Widevine protobuf
raw                Raw bits
tar                Tar archive
tiff               Tag Image File Format
vorbis_comment     Vorbis comment
vorbis_packet      Vorbis packet
vp8_frame          VP8 frame
vp9_cfm            VP9 Codec Feature Metadata
vp9_frame          VP9 frame
vpx_ccr            VPX Codec Configuration Record
wav                WAV file
webp               WebP image
xing               Xing header
$ fq -X
exitcode: 2
stderr:
error: -X: no such argument
$ fq --X
exitcode: 2
stderr:
error: --X: no such argument
$ fq -.
exitcode: 2
stderr:
error: -.: no such argument