fstinfo(1)

💖 fstinfo 💖

okay bestie, gather round, because fstinfo(1) is here and she is serving info about your FSTs ✨. This is the user-commands page for her, so let's get into it 💅

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🌸 NAME 🌸

fstinfo — shows you info about an FST 🫶

✨ SYNOPSIS ✨

fstinfo [OPTIONS] [in.fst]

💜 DESCRIPTION 💜

She prints out information about an FST. That's it, that's the job, and she does it beautifully 😌 no cap.

🎀 OPTIONS 🎀

real talk first: boolean options can take either true or false as a value, OR you can just say the option and it's implicitly true if you don't give a value at all. lowkey convenient, highkey iconic 💫

• --arc_filter=TYPE — Sets the arc filter, and TYPE is one of any, epsilon, iepsilon, and oepsilon. Heads up though: this only changes the counts of (co)accessible states, connected states, and (strongly) connected components. Default: any.
• --fst_align[=BOOLEAN] — Writes FST data aligned where appropriate. Default: false.
• --fst_compat_symbols[=BOOLEAN] — Makes it require symbol tables to match when appropriate. Default: true.
• --fst_default_cache_gc[=BOOLEAN] — Enables garbage collection of the cache 🗑️✨. Default: true.
• --fst_default_cache_gc_limit=N — Sets the cache byte size that triggers garbage collection. Default: 1048576.
• --fst_error_fatal[=BOOLEAN] — If it's true, FST errors are fatal 💀. Otherwise the returned objects get flagged as bad instead — like, FSTs come back with the kError property set to true, and FST weights get set so that Member() returns false. Default: true.
• --fst_field_separator=STRING — Sets the characters used as a separator between printed fields. Default: " ".
• --fst_read_mode=STRING — Sets the default file reading mode for mappable files, either "read" or "map". Default: "read".
• --fst_verify[=BOOLEAN] — Verifies FST sanity. Default: true.
• --fst_verify_properties[=BOOLEAN] — Verifies fst properties queried by TestProperties. Default: false.
• --fst_weight_parentheses=STRING — Sets the characters enclosing the first weight of a printed composite weight (think pair weight, tuple weight, and derived classes) so that nested composite weights I/O properly. It must have size 0 (none) or 2 (open and close parenthesis). Default: no parentheses.
• --fst_weight_separator=CHARACTER — Sets the character separator between printed composite weights. Default: comma.
• --help[=BOOLEAN] — Shows usage information. Default: false.
• --helpshort[=BOOLEAN] — Shows brief usage information. Default: false.
• --info_type=TYPE — Sets the info format, one of auto, long, and short. Default: auto.
• --pipe[=BOOLEAN] — Sends information to stderr, and input to stdout 🌀. Default: false.
• --save_relabel_ipairs=FILENAME — Saves input relabel pairs to a file. Default: do not save.
• --save_relabel_opairs=FILENAME — Saves output relabel pairs to a file. Default: do not save.
• --test_properties[=BOOLEAN] — Computes property values (if unknown to FST). Default: true.
• --tmpdir=PATHNAME — Sets the temporary directory to use. Default: /tmp.
• --v[=N] — Sets the verbosity level. Default: 0.

🦋 SEE ALSO 🦋

the whole friend group showed up, they all ate fr fr 🙈💖

fstarcsort(1), fstclosure(1), fstcompile(1), fstcompose(1), fstcompress(1), fstconcat(1), fstconnect(1), fstconvert(1), fstdeterminize(1), fstdifference(1), fstdisambiguate(1), fstdraw(1), fstencode(1), fstepsnormalize(1), fstequal(1), fstequivalent(1), fstintersect(1), fstinvert(1), fstisomorphic(1), fstlinear(1), fstloglinearapply(1), fstmap(1), fstminimize(1), fstprint(1), fstproject(1), fstprune(1), fstpush(1), fstrandgen(1), fstrelabel(1), fstreplace(1), fstreverse(1), fstreweight(1), fstrmepsilon(1), fstshortestdistance(1), fstshortestpath(1), fstsymbols(1), fstsynchronize(1), fsttopsort(1), fstunion(1)

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okay that's the whole page bestie, go forth and fstinfo responsibly 👑💅

and for the lil sign-off — this one's from OpenFst 1.8.5, dated Mar 2026 🌈⭐ mwah, love u, bye 🫶