Command reference

Every fx- command, generated from its Dhall schema. The schema is the single source of truth: the same declaration produces the POSIX parser, the typed Dhall-record form, and this page.

See the README for how to add a command, or concept.md for the design.

`fx-basename`strip directories and any suffix from file names

usage: fx-basename [OPTIONS] [NAME] [SUFFIX]

field	type	default	flag / operand
`all`	`Bool`	`False`	`-a, --multiple`
`input`	`Text`	`""`	`NAME`
`names`	`List Text`	`[]`	—
`suffix`	`Text`	`""`	`SUFFIX`

`fx-cat`concatenate FILEs (or stdin) to stdout, bytes to bytes

usage: fx-cat [FILE...]

field	type	default	flag / operand
`files`	`List Text`	`[]`	`FILE …`

`fx-chgrp`change the group ownership of files (datalog-backed stat rows)

usage: fx-chgrp [GROUP] [FILE...]

field	type	default	flag / operand
`group`	`Text`	`""`	`GROUP`
`paths`	`List Text`	`[]`	`FILE …`

`fx-chmod`change file mode bits, journaled through the derivation log

usage: fx-chmod [MODE] [FILE...]

field	type	default	flag / operand
`mode`	`Text`	`""`	`MODE`
`paths`	`List Text`	`[]`	`FILE …`

`fx-chown`change the owner and/or group of files (datalog-backed stat rows)

usage: fx-chown [OWNER] [FILE...]

field	type	default	flag / operand
`owner`	`Text`	`""`	`OWNER`
`paths`	`List Text`	`[]`	`FILE …`

`fx-cksum`print CRC checksum (POSIX) and byte count for each FILE

usage: fx-cksum [FILE...]

field	type	default	flag / operand
`files`	`List Text`	`[]`	`FILE …`

`fx-comm`compare two sorted files line by line (three-column output)

usage: fx-comm [OPTIONS] [FILE1] [FILE2]

field	type	default	flag / operand
`a`	`Text`	`""`	`FILE1`
`b`	`Text`	`""`	`FILE2`
`one`	`Bool`	`False`	`-1, --suppress-1`
`three`	`Bool`	`False`	`-3, --suppress-3`
`two`	`Bool`	`False`	`-2, --suppress-2`

`fx-cp`copy files, capturing originals to CAS before mutating

usage: fx-cp [SRC] [DST]

field	type	default	flag / operand
`dst`	`Text`	`""`	`DST`
`src`	`Text`	`""`	`SRC`

`fx-date`print or set the system date and time (UTC)

usage: fx-date [OPTIONS]

field	type	default	flag / operand
`format`	`Text`	`"%a %b %e %H:%M:%S %Z %Y"`	—
`utc`	`Bool`	`False`	`-u, --utc`

`fx-df`report filesystem usage in 1K blocks via statvfs

usage: fx-df [OPTIONS] [PATH]

field	type	default	flag / operand
`path`	`Text`	`""`	`PATH`
`rows`	`Bool`	`False`	`--rows`

`fx-diff`compare two files (or trees, -r) line by line

usage: fx-diff [OPTIONS] [A] [B]

field	type	default	flag / operand
`a`	`Text`	`""`	`A`
`b`	`Text`	`""`	`B`
`recursive`	`Bool`	`False`	`-r, --recursive`

`fx-dirname`strip the last component from a file name

usage: fx-dirname [NAME...]

field	type	default	flag / operand
`names`	`List Text`	`[]`	`NAME …`

`fx-du`estimate file space usage as Datalog-backed stat rows

usage: fx-du [OPTIONS] [PATH]

field	type	default	flag / operand
`maxdepth`	`Optional Natural`	`None`	`-d, --max-depth` N
`path`	`Text`	`"."`	`PATH`
`rows`	`Bool`	`False`	`--rows`
`summary`	`Bool`	`False`	`-s, --summarize`

`fx-echo`print the given STRINGs to stdout, newline-terminated

usage: fx-echo [OPTIONS] [STRING...]

field	type	default	flag / operand
`escapes`	`Bool`	`False`	`-e`
`no_newline`	`Bool`	`False`	`-n`
`strings`	`List Text`	`[]`	`STRING …`

`fx-env`print, filter or modify the environment, then run nothing (print form)

usage: fx-env [OPTIONS] [NAME=VALUE...]

field	type	default	flag / operand
`ignore`	`Bool`	`False`	`-i, --ignore-environment`
`sets`	`List Text`	`[]`	`NAME=VALUE …`
`unset`	`Optional Text`	`None`	`-u, --unset` TEXT

`fx-expand`convert tabs in FILEs (or stdin) to spaces

usage: fx-expand [OPTIONS] [FILE...]

field	type	default	flag / operand
`files`	`List Text`	`[]`	`FILE …`
`tabstop`	`Natural`	`8`	`-t, --tabs` N

`fx-find`walk a directory closure via Datalog reachability from ROOT

usage: fx-find [ROOT]

field	type	default	flag / operand
`maxdepth`	`Optional Natural`	`None`	—
`name_glob`	`Optional Text`	`None`	—
`root`	`Text`	`"."`	`ROOT`
`type_filter`	`Optional < Dir \| File >`	`None`	—

`fx-grep`print lines of files under ROOT matching a regex PATTERN

usage: fx-grep [PATTERN] [ROOT]

field	type	default	flag / operand
`maxdepth`	`Optional Natural`	`None`	—
`name_glob`	`Optional Text`	`None`	—
`pattern`	`Text`	`""`	`PATTERN`
`root`	`Text`	`"."`	`ROOT`

`fx-head`print the first N lines (-n, default 10) of FILEs (or stdin)

usage: fx-head [OPTIONS] [FILE]

field	type	default	flag / operand
`input`	`Text`	`""`	`FILE`
`n`	`Natural`	`10`	`-n, --lines` N

`fx-hostname`print the system's host name

usage: fx-hostname

field	type	default	flag / operand
`nothing`	`Bool`	`True`	—

`fx-id`print user and group identity for USER (or the caller)

usage: fx-id [OPTIONS] [USER]

field	type	default	flag / operand
`all`	`Bool`	`False`	`-G`
`gid`	`Bool`	`False`	`-g`
`names`	`Bool`	`False`	`-n`
`real`	`Bool`	`False`	`-r`
`uid`	`Bool`	`False`	`-u`
`user`	`Text`	`""`	`USER`

Mutually exclusive: -u -g -G

`fx-link`create a hard link OLD -> NEW via linkat, journaled

usage: fx-link [OLD] [NEW]

field	type	default	flag / operand
`new`	`Text`	`""`	`NEW`
`old`	`Text`	`""`	`OLD`

`fx-ln`create links between files (-s for symbolic)

usage: fx-ln [OPTIONS] [TARGET] [LINK_NAME]

field	type	default	flag / operand
`dst`	`Text`	`""`	`LINK_NAME`
`src`	`Text`	`""`	`TARGET`
`symbolic`	`Bool`	`False`	`-s, --symbolic`

`fx-ls`list a directory's entries as Datalog-backed stat rows

usage: fx-ls [OPTIONS] [PATH]

field	type	default	flag / operand
`all`	`Bool`	`False`	`-a, --all`
`long`	`Bool`	`False`	`-l, --long`
`path`	`Text`	`"."`	`PATH`
`rows`	`Bool`	`False`	`--rows`
`sort`	`< MTime \| Name \| Size >`	`< MTime \| Name \| Size >.Name`	`-S` `-t`

Mutually exclusive: -S -t

`fx-md5sum`print or check MD5 (128-bit) checksums

usage: fx-md5sum [OPTIONS] [FILE...]

field	type	default	flag / operand
`binary`	`Bool`	`False`	`-b, --binary`
`files`	`List Text`	`[]`	`FILE …`

`fx-mkdir`create directories (-p for parents), journaled

usage: fx-mkdir [OPTIONS] [DIR...]

field	type	default	flag / operand
`parents`	`Bool`	`False`	`-p, --parents`
`paths`	`List Text`	`[]`	`DIR …`

`fx-mkfifo`create FIFOs with mkfifo(3), -m sets the mode

usage: fx-mkfifo [OPTIONS] [NAME...]

field	type	default	flag / operand
`mode`	`Optional Text`	`None`	`-m, --mode` TEXT
`paths`	`List Text`	`[]`	`NAME …`

`fx-mv`rename SOURCE to DEST, or move SOURCE into DIRECTORY

usage: fx-mv [SRC] [DST]

field	type	default	flag / operand
`dst`	`Text`	`""`	`DST`
`src`	`Text`	`""`	`SRC`

`fx-nl`number lines of a file or stdin (GNU nl)

usage: fx-nl [OPTIONS] [FILE]

field	type	default	flag / operand
`body`	`Text`	`"t"`	`-b, --body-numbering` TEXT
`file`	`Text`	`""`	`FILE`
`fmt`	`Text`	`"rn"`	`-n, --number-format` TEXT
`sep`	`Text`	`" "`	`-s, --number-separator` TEXT
`width`	`Natural`	`6`	`-w, --number-width` N

`fx-paste`merge corresponding or subsequent lines of files (GNU paste)

usage: fx-paste [OPTIONS] [FILE...]

field	type	default	flag / operand
`delim`	`Text`	`" "`	`-d, --delimiters` TEXT
`files`	`List Text`	`[]`	`FILE …`
`serial`	`Bool`	`False`	`-s, --serial`

`fx-ps`snapshot running processes as a datalog-backed view

usage: fx-ps [OPTIONS]

field	type	default	flag / operand
`rows`	`Bool`	`False`	`--rows`
`sort`	`< Cpu \| Mem \| Pid >`	`< Cpu \| Mem \| Pid >.Pid`	`-c` `-m`

Mutually exclusive: -c -m

`fx-realpath`print the resolved absolute file name

usage: fx-realpath [FILE...]

field	type	default	flag / operand
`names`	`List Text`	`[]`	`FILE …`

`fx-rm`remove files or directories (-r), journaled with CAS capture

usage: fx-rm [OPTIONS] [FILE...]

field	type	default	flag / operand
`paths`	`List Text`	`[]`	`FILE …`
`recursive`	`Bool`	`False`	`-r, --recursive`

`fx-rmdir`remove empty directories, journaled

usage: fx-rmdir [DIR...]

field	type	default	flag / operand
`paths`	`List Text`	`[]`	`DIR …`

`fx-seq`print a sequence of numbers FIRST..LAST (step INC)

usage: fx-seq

field	type	default	flag / operand
`first`	`Integer`	`1`	—
`inc`	`Integer`	`1`	—
`last`	`Integer`	`0`	—

`fx-sha1sum`print or check SHA-1 (160-bit) checksums

usage: fx-sha1sum [OPTIONS] [FILE...]

field	type	default	flag / operand
`binary`	`Bool`	`False`	`-b, --binary`
`files`	`List Text`	`[]`	`FILE …`

`fx-sha224sum`print or check SHA-224 checksums

usage: fx-sha224sum [OPTIONS] [FILE...]

field	type	default	flag / operand
`binary`	`Bool`	`False`	`-b, --binary`
`files`	`List Text`	`[]`	`FILE …`

`fx-sha256sum`print or check SHA-256 checksums

usage: fx-sha256sum [OPTIONS] [FILE...]

field	type	default	flag / operand
`binary`	`Bool`	`False`	`-b, --binary`
`files`	`List Text`	`[]`	`FILE …`

`fx-sha384sum`print or check SHA-384 checksums

usage: fx-sha384sum [OPTIONS] [FILE...]

field	type	default	flag / operand
`binary`	`Bool`	`False`	`-b, --binary`
`files`	`List Text`	`[]`	`FILE …`

`fx-sha512sum`print or check SHA-512 checksums

usage: fx-sha512sum [OPTIONS] [FILE...]

field	type	default	flag / operand
`binary`	`Bool`	`False`	`-b, --binary`
`files`	`List Text`	`[]`	`FILE …`

`fx-sort`sort lines (numeric, reverse, unique) as Datalog-backed rows

usage: fx-sort [OPTIONS] [FILE]

field	type	default	flag / operand
`input`	`Text`	`""`	`FILE`
`numeric`	`Bool`	`False`	`-n, --numeric-sort`
`reverse`	`Bool`	`False`	`-r, --reverse`
`unique`	`Bool`	`False`	`-u, --unique`

`fx-sum`print checksum and block count for each FILE (-s SysV)

usage: fx-sum [OPTIONS] [FILE...]

field	type	default	flag / operand
`files`	`List Text`	`[]`	`FILE …`
`sysv`	`Bool`	`False`	`-s, --sysv`

`fx-tail`print the last N lines (-n, default 10) of FILEs (or stdin)

usage: fx-tail [OPTIONS] [FILE]

field	type	default	flag / operand
`input`	`Text`	`""`	`FILE`
`n`	`Natural`	`10`	`-n, --lines` N

`fx-tee`copy stdin to each FILE and to stdout (-a appends)

usage: fx-tee [OPTIONS] [FILE...]

field	type	default	flag / operand
`append`	`Bool`	`False`	`-a, --append`
`files`	`List Text`	`[]`	`FILE …`

`fx-top`single-shot process ranking by total cpu ticks or memory

usage: fx-top [OPTIONS]

field	type	default	flag / operand
`count`	`Natural`	`15`	`-n` N
`rows`	`Bool`	`False`	`--rows`
`sort`	`< Cpu \| Mem >`	`< Cpu \| Mem >.Cpu`	`-m`

`fx-touch`create files or update timestamps, journaled

usage: fx-touch [FILE...]

field	type	default	flag / operand
`files`	`List Text`	`[]`	`FILE …`

`fx-tree`render a directory closure as a tree (Datalog descent)

usage: fx-tree [OPTIONS] [ROOT]

field	type	default	flag / operand
`all`	`Bool`	`False`	`-a, --all`
`dirs_only`	`Bool`	`False`	`-d, --dirs-only`
`maxdepth`	`Optional Natural`	`None`	`-L` N
`root`	`Text`	`"."`	`ROOT`
`rows`	`Bool`	`False`	`--rows`

`fx-truncate`shrink or extend a file to SIZE (-r REF), CAS-captured

usage: fx-truncate [OPTIONS] [FILE...]

field	type	default	flag / operand
`files`	`List Text`	`[]`	`FILE …`
`no_create`	`Bool`	`False`	`-c, --no-create`
`ref`	`Optional Text`	`None`	`-r, --reference` TEXT
`size`	`Optional Text`	`None`	`-s, --size` TEXT

Mutually exclusive: -s -r

`fx-uname`print system information (-a: all)

usage: fx-uname [OPTIONS]

field	type	default	flag / operand
`all`	`Bool`	`False`	`-a, --all`
`kernel`	`Bool`	`False`	`-s, --kernel-name`
`machine`	`Bool`	`False`	`-m, --machine`
`nodename`	`Bool`	`False`	`-n, --nodename`
`os`	`Bool`	`False`	`-o, --operating-system`
`release`	`Bool`	`False`	`-r, --release`
`version`	`Bool`	`False`	`-v`

`fx-uniq`filter repeated adjacent lines in sorted input (-c counts)

usage: fx-uniq [OPTIONS] [FILE]

field	type	default	flag / operand
`count`	`Bool`	`False`	`-c, --count`
`global`	`Bool`	`False`	`-g, --global`
`input`	`Text`	`""`	`FILE`

`fx-unlink`delete a name and possibly the file it refers to

usage: fx-unlink [PATH]

field	type	default	flag / operand
`path`	`Text`	`""`	`PATH`

`fx-wc`print newline, word and byte counts for each FILE

usage: fx-wc [FILE]

field	type	default	flag / operand
`input`	`Text`	`""`	`FILE`

`fx-what`query which package owns a rootfs PATH (provenance)

usage: fx-what [OPTIONS] [PATH]

field	type	default	flag / operand
`as_of`	`Optional Natural`	`None`	`--as-of` N
`operand`	`Text`	`""`	`PATH`
`store`	`Optional Text`	`None`	`--store` TEXT

`fx-whoami`print the effective user name

usage: fx-whoami

field	type	default	flag / operand
`nothing`	`Bool`	`True`	—

`fx-why`explain why a package is in the store (provenance)

usage: fx-why [OPTIONS] [PKG]

field	type	default	flag / operand
`as_of`	`Optional Natural`	`None`	`--as-of` N
`operand`	`Text`	`"."`	`PKG`
`store`	`Optional Text`	`None`	`--store` TEXT

`fx-yes`repeatedly output STRING (or 'y'), one per line, until killed

usage: fx-yes [STRING...]

field	type	default	flag / operand
`strings`	`List Text`	`[]`	`STRING …`

Command reference

fx-basenamestrip directories and any suffix from file names

fx-catconcatenate FILEs (or stdin) to stdout, bytes to bytes

fx-chgrpchange the group ownership of files (datalog-backed stat rows)

fx-chmodchange file mode bits, journaled through the derivation log

fx-chownchange the owner and/or group of files (datalog-backed stat rows)

fx-cksumprint CRC checksum (POSIX) and byte count for each FILE

fx-commcompare two sorted files line by line (three-column output)

fx-cpcopy files, capturing originals to CAS before mutating

fx-dateprint or set the system date and time (UTC)

fx-dfreport filesystem usage in 1K blocks via statvfs

fx-diffcompare two files (or trees, -r) line by line

fx-dirnamestrip the last component from a file name

fx-duestimate file space usage as Datalog-backed stat rows

fx-echoprint the given STRINGs to stdout, newline-terminated

fx-envprint, filter or modify the environment, then run nothing (print form)

fx-expandconvert tabs in FILEs (or stdin) to spaces

fx-findwalk a directory closure via Datalog reachability from ROOT

fx-grepprint lines of files under ROOT matching a regex PATTERN

fx-headprint the first N lines (-n, default 10) of FILEs (or stdin)

fx-hostnameprint the system's host name

fx-idprint user and group identity for USER (or the caller)

fx-linkcreate a hard link OLD -> NEW via linkat, journaled

fx-lncreate links between files (-s for symbolic)

fx-lslist a directory's entries as Datalog-backed stat rows

fx-md5sumprint or check MD5 (128-bit) checksums

fx-mkdircreate directories (-p for parents), journaled

fx-mkfifocreate FIFOs with mkfifo(3), -m sets the mode

fx-mvrename SOURCE to DEST, or move SOURCE into DIRECTORY

fx-nlnumber lines of a file or stdin (GNU nl)

fx-pastemerge corresponding or subsequent lines of files (GNU paste)

fx-pssnapshot running processes as a datalog-backed view

fx-realpathprint the resolved absolute file name

fx-rmremove files or directories (-r), journaled with CAS capture

fx-rmdirremove empty directories, journaled

fx-seqprint a sequence of numbers FIRST..LAST (step INC)

fx-sha1sumprint or check SHA-1 (160-bit) checksums

fx-sha224sumprint or check SHA-224 checksums

fx-sha256sumprint or check SHA-256 checksums

fx-sha384sumprint or check SHA-384 checksums

fx-sha512sumprint or check SHA-512 checksums

fx-sortsort lines (numeric, reverse, unique) as Datalog-backed rows

fx-sumprint checksum and block count for each FILE (-s SysV)

fx-tailprint the last N lines (-n, default 10) of FILEs (or stdin)

fx-teecopy stdin to each FILE and to stdout (-a appends)

fx-topsingle-shot process ranking by total cpu ticks or memory

fx-touchcreate files or update timestamps, journaled

fx-treerender a directory closure as a tree (Datalog descent)

fx-truncateshrink or extend a file to SIZE (-r REF), CAS-captured

fx-unameprint system information (-a: all)

fx-uniqfilter repeated adjacent lines in sorted input (-c counts)

fx-unlinkdelete a name and possibly the file it refers to

fx-wcprint newline, word and byte counts for each FILE

fx-whatquery which package owns a rootfs PATH (provenance)

fx-whoamiprint the effective user name

fx-whyexplain why a package is in the store (provenance)

fx-yesrepeatedly output STRING (or 'y'), one per line, until killed