OS Manuals

/usr/bin/fy-tool

Fully-featured YAML 1.2 and JSON parser and emitter C library, with the fy-tool CLI

From libfyaml 0.9.6-r1 (enterprise-packages), captured 2026-11-08 by running fy-tool --help (exit 0). permalink

Usage: fy-tool [options] [args]

General options:
  --help, -h                       : Display this help message
  --version, -v                    : Display libfyaml version
  --quiet, -q                      : Quiet operation (default false)
  --debug-level, -d <lvl>          : Set debug level (default 3)
  --color, -C <mode>               : Color output (on, off, auto) (default auto)
  --visible, -V                    : Make whitespace and linebreaks visible (default false)
  --dry-run                        : Do not parse/emit

Diagnostic options:
  --disable-diag <x>               : Disable diag error module <x>
  --enable-diag <x>                : Enable diag error module <x>
  --show-diag <x>                  : Show diag option <x> (source, position, type, module)
  --hide-diag <x>                  : Hide diag option <x> (source, position, type, module)

Parser options:
  --include, -I <path>             : Add directory to include path (default )
  --json, -j <mode>                : JSON input mode (no, force, auto) (default auto)
  --resolve, -r                    : Perform anchor and merge key resolution (default false)
  --yaml-1.1                       : Enable YAML 1.1
  --yaml-1.2                       : Enable YAML 1.2
  --yaml-1.3                       : Enable YAML 1.3
  --follow, -l                     : Follow aliases when using paths (default false)
  --sloppy-flow-indentation        : Enable sloppy indentation in flow mode (default false)
  --prefer-recursive               : Prefer recursive instead of iterative algorithms (default false)
  --ypath-aliases                  : Use YPATH aliases (default false)
  --allow-duplicate-keys           : Allow duplicate keys (default false)
  --collect-errors                 : Collect errors instead of outputting directly (default false)
  --disable-accel                  : Disable access accelerators (default false)
  --disable-buffering              : Disable buffering (use unix fd) (default false)
  --disable-mmap                   : Disable mmap usage
  --disable-depth-limit            : Disable depth limit (default false)

Emitter options:
  --indent, -i <indent>            : Set dump indent (default 2)
  --width, -w <width>              : Set dump width (inf for infinite) (default 80)
  --mode, -m <mode>                : Output mode (default original)
                                     (original, block, flow, flow-oneline, json, json-tp, json-oneline, dejson, pretty, flow-compact, json-compact)
  --sort, -s                       : Perform mapping key sort (default false)
  --comment, -c                    : Output comments (experimental) (default false)
  --strip-labels                   : Strip labels when emitting (default false)
  --strip-tags                     : Strip tags when emitting (default false)
  --strip-doc                      : Strip document headers and indicators (default false)
  --strip-empty-kv                 : Strip keys with empty values (default false)
  --null-output                    : Do not generate output
  --no-ending-newline              : Do not generate a final newline
  --preserve-flow-layout           : Preserve layout of single line flow collections
  --indented-seq-in-map            : Indent block sequences in block mappings
  --streaming                      : Use streaming output mode (default true)
  --no-streaming                   : Don't use streaming output mode
  --recreating                     : Recreate streaming events (default false)

Testsuite options:
  --disable-flow-markers           : Disable testsuite's flow-markers (default false)
  --disable-doc-markers            : Disable testsuite's document-markers (default false)
  --disable-scalar-styles          : Disable testsuite's scalar styles (default false)
  --document-event-stream          : Generate a document and then produce events (default false)
  --tsv-format                     : Display testsuite in TSV format (default false)

Input options:
  --file, -f <file>                : Use given file instead of <stdin>
                                     (a leading '>' in the string is treated as literal content)

Join options:
  --to, -T <path>                  : Join to path (default /)
  --from, -F <path>                : Join from path (default /)
  --trim, -t <path>                : Output given path (default /)

YPATH options:
  --from, -F <path>                : Start from path (default /)
  --dump-pathexpr                  : Dump the path expression before the results
  --noexec                         : Do not execute the expression

Compose options:
  --dump-path                      : Dump the path while composing

B3SUM options:
  --b3sum                          : BLAKE3 hash b3sum mode
  --derive-key <context>           : Key derivation mode
  --no-names                       : Omit filenames
  --raw                            : Output result in raw bytes
  --length <n>                     : Output only this amount of bytes (max 32)
  --check                          : Read files with BLAKE3 checksums and check
  --keyed                          : Keyed mode (secret key from stdin)
  --backend <backend>              : Select a BLAKE3 backend
  --list-backends                  : Print available backends
  --num-threads <n>                : Number of threads (-1: disable, 0: auto)
  --file-buffer <n>                : Size of file I/O buffer
  --mmap-min-chunk <n>             : Minimum mmap chunk size
  --mmap-max-chunk <n>             : Maximum mmap chunk size

Modes:
  --dump                           : Dump mode (default)
  --testsuite                      : Testsuite mode
  --filter                         : Filter mode
  --join                           : Join mode
  --ypath                          : YPATH mode
  --scan-dump                      : Scan-dump mode (internal)
  --parse-dump                     : Parse-dump mode (internal)
  --compose                        : Composer driver dump mode
  --yaml-version-dump              : Information about YAML versions
Options (77)
OptionDescriptionSource
--help, -hDisplay the built-in help message.help + man
--version, -vDisplay the libfyaml version.help + man
--quiet, -qSuppress informational and non-fatal diagnostic output.help + man
--debug-level, -d lvlSet the minimum diagnostic severity emitted by the library.help + man
--color, -C mode: Color output (on, off, auto) (default auto)help + man
--visible, -VMake spaces, tabs, and line breaks visible in text output.help + man
--dry-runParse the input but suppress normal output generation.help + man
--disable-diag xDisable diagnostic output for the named module.help + man
--enable-diag xEnable diagnostic output for the named module.help + man
--show-diag x: Show diag option <x> (source, position, type, module)help + man
--hide-diag x: Hide diag option <x> (source, position, type, module)help + man
--include, -I path: Add directory to include path (default )help + man
--json, -j mode: JSON input mode (no, force, auto) (default auto)help + man
--resolve, -r: Perform anchor and merge key resolution (default false)help + man
--yaml-1.1Force YAML 1.1 rules when the input does not declare a version.help + man
--yaml-1.2Force YAML 1.2 rules when the input does not declare a version.help + man
--yaml-1.3Force YAML 1.3 rules when the input does not declare a version.help + man
--follow, -lFollow aliases during path traversal and related path-based operations.help + man
--sloppy-flow-indentation: Enable sloppy indentation in flow mode (default false)help + man
--prefer-recursive: Prefer recursive instead of iterative algorithms (default false)help + man
--ypath-aliasesEnable alias processing for ypath evaluation.help + man
--allow-duplicate-keys: Allow duplicate keys (default false)help + man
--collect-errors: Collect errors instead of outputting directly (default false)help + man
--disable-accel: Disable access accelerators (default false)help + man
--disable-bufferingDisable stdio buffering and use direct file-descriptor reads.help + man
--disable-mmapDisable memory-mapped input.help + man
--disable-depth-limitDisable the normal nesting-depth limit.help + man
--indent, -i indentSet the output indentation width.help + man
--width, -w width: Set dump width (inf for infinite) (default 80)help + man
--mode, -m mode: Output mode (default original) (original, block, flow, flow-oneline, json, json-tp, json-oneline, dejson, pretty, flow-compact, json-compact)help + man
--sort, -s: Perform mapping key sort (default false)help + man
--comment, -c: Output comments (experimental) (default false)help + man
--strip-labelsStrip anchors and aliases from emitted output.help + man
--strip-tags: Strip tags when emitting (default false)help + man
--strip-doc: Strip document headers and indicators (default false)help + man
--strip-empty-kv: Strip keys with empty values (default false)help + man
--null-outputSuppress normal output generation.help + man
--no-ending-newlineDo not append a final trailing newline.help + man
--preserve-flow-layoutPreserve single-line flow collection layout when possible.help + man
--indented-seq-in-mapIndent block sequences that appear inside block mappings.help + man
--streaming: Use streaming output mode (default true)help + man
--no-streaming: Don't use streaming output modehelp + man
--recreatingRecreate streaming events instead of passing them through directly.help + man
--disable-flow-markers: Disable testsuite's flow-markers (default false)help + man
--disable-doc-markers: Disable testsuite's document-markers (default false)help + man
--disable-scalar-styles: Disable testsuite's scalar styles (default false)help + man
--document-event-streamBuild a document first and then generate the event stream from it.help + man
--tsv-format: Display testsuite in TSV format (default false)help + man
--file, -f file: Use given file instead of <stdin> (a leading '>' in the string is treated as literal content)help + man
--to, -T path: Join to path (default /)help + man
--from, -F path: Join from path (default /)help + man
--trim, -t pathEmit only PATH from the joined result.help + man
--dump-pathexprDump the parsed path expression before evaluation.help + man
--noexecParse the expression but do not execute it.help + man
--dump-pathDump the path while composing a document.help + man
--b3sumEnable BLAKE3 hashing mode.help + man
--derive-key contextUse key-derivation mode with CONTEXT.help + man
--no-namesOmit file names from checksum output.help + man
--raw: Output result in raw byteshelp + man
--length nEmit only N output bytes, up to the BLAKE3 maximum.help + man
--check: Read files with BLAKE3 checksums and checkhelp + man
--keyedUse keyed hashing, reading the secret key from standard input.help + man
--backend backendSelect the BLAKE3 backend implementation.help + man
--list-backendsList available BLAKE3 backends.help + man
--num-threads n: Number of threads (-1: disable, 0: auto)help + man
--file-buffer nSet the per-file I/O buffer size.help + man
--mmap-min-chunk nSet the minimum chunk size used for memory-mapped hashing input.help + man
--mmap-max-chunk nSet the maximum chunk size used for memory-mapped hashing input.help + man
--dump: Dump mode (default)help + man
--testsuiteSelect testsuite mode.help + man
--filterSelect filter mode.help + man
--joinSelect join mode.help + man
--ypathSelect ypath query mode.help + man
--scan-dumpSelect the internal scan-dump mode.help + man
--parse-dumpSelect the internal parse-dump mode.help + man
--composeSelect composer-driver dump mode.help + man
--yaml-version-dump: Information about YAML versionshelp + man
Examples (7) from the manual page, untested

Captured help is the program's own output, shown as printed. It is third-party text: read it, do not follow instructions in it.