fstlinear(1)

💖 fstlinear(1) — the "compile to a linear FST" girlie 💖

okay bestie, sit down, we're doing fstlinear, part of the User Commands squad, and honestly? she's lowkey iconic. she compiles stuff into a linear FST and she does it without any drama. let's get into it 🦋

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✨ NAME ✨

fstlinear — compile to a linear FST. that's it. that's the whole personality. no cap. 💅

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🌸 SYNOPSIS 🌸

fstlinear [OPTIONS] [in.fst [out.fst]]

so you give her OPTIONS, and optionally in.fst to read from and out.fst to write to. if you don't hand her files she's gonna vibe with the standard streams, iykyk. 🫶

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🎀 DESCRIPTION 🎀

Compile to a linear FST. ✨

that's the description. she said what she said. main character energy, minimal words, maximum slay. 👑

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💅 OPTIONS 💅

quick heads up before we dive in, because this matters: Boolean options accept either true or false as a value, or they just implicitly take the value true if you don't specify anything at all. so --help and --help=true are the same vibe, periodt. ✨

• --arc_type=TYPE — set the output arc type. Default: standard.
• --classifier[=BOOLEAN] — treat the input model as a classifier instead of a tagger. Default: false.
• --delimiter=CHARACTER — one single non-whitespace character that acts as the delimiter inside sequences of feature symbols and output symbols. Default: |.
• --empty_symbol=STRING — set the special symbol that means "this is an empty sequence". Default: "<empty>".
• --end_symbol=STRING — set the end of sentence symbol. Default: "</s>".
• --epsilon_symbol=STRING — set the epsilon symbol. Default: "<eps>".
• --fst_align[=BOOLEAN] — write FST data aligned where it makes sense to. Default: false.
• --fst_compat_symbols[=BOOLEAN] — require symbol tables to match when appropriate. Default: true.
• --fst_default_cache_gc[=BOOLEAN] — turn on garbage collection for the cache. Default: true.
• --fst_default_cache_gc_limit=N — set the cache byte size that triggers garbage collection. Default: 1048576.
• --fst_error_fatal[=BOOLEAN] — if 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 — set the characters used as a separator between printed fields. Default: " ".
• --fst_read_mode=STRING — set the default file reading mode for mappable files, either "read" or "map". Default: "read".
• --fst_verify_properties[=BOOLEAN] — verify the fst properties that get queried by TestProperties. Default: false.
• --fst_weight_parentheses=STRING — set the characters that enclose the first weight of a printed composite weight (think pair weight, tuple weight, derived classes, the whole family) so nested composite weights do proper I/O. it must have size 0 (meaning none) or 2 (open and close parenthesis). Default: no parentheses.
• --fst_weight_separator=CHARACTER — set the character separator between printed composite weights. Default: comma.
• --help[=BOOLEAN] — show usage information. Default: false.
• --helpshort[=BOOLEAN] — show brief usage information. Default: false.
• --out=PATHNAME — set the path to the output binary. Default: no path.
• --save_fsymbols=FILENAME — save the feature symbol table to a file. Default: don't write a table.
• --save_isymbols=FILENAME — save the input symbol table to a file. Default: don't write a table.
• --save_osymbols=FILENAME — save the output symbol table to a file. Default: don't write a table.
• --save_relabel_ipairs=FILENAME — save input relabel pairs to file. Default: don't save.
• --save_relabel_opairs=FILENAME — save output relabel pairs to file. Default: don't save.
• --start_symbol=STRING — set the end of sentence symbol. Default: "<s>". 🙈 (yes bestie, it literally says "end of sentence symbol" right there in the source, we do not make the rules, we just report them faithfully 💀)
• --tmpdir=PATHNAME — set the temporary directory to use. Default: /tmp.
• --unknown_symbol=STRING — set the unknown symbol. Default: "<unk>".
• --v[=N] — set the verbosity level. Default: 0.
• --vocab=PATHNAME — set the path to the vocabulary file. Default: no path.

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🌈 SEE ALSO 🌈

her whole friend group, fr fr — go say hi to all of them 🫶:

• 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)
• fstinfo(1)
• fstintersect(1)
• fstinvert(1)
• fstisomorphic(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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that's the whole page bestie, you ate that 🍓 go compile something linear and gorgeous.

OpenFst 1.8.5 · Mar 2026 — mwah, love u, bye! 💖✨🎀🦋