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zstd(1)                           User Commands                          zstd(1)


       zstd - zstd, zstdmt, unzstd, zstdcat - Compress or decompress .zst files


       zstdmt is equivalent to zstd -T0

       unzstd is equivalent to zstd -d

       zstdcat is equivalent to zstd -dcf


       zstd is a fast lossless compression algorithm and data compression tool,
       with command line syntax similar to gzip(1) and xz(1). It is based on the
       LZ77 family, with further FSE & huff0 entropy stages. zstd offers highly
       configurable compression speed, from fast modes at > 200 MB/s per core,
       to strong modes with excellent compression ratios. It also features a
       very fast decoder, with speeds > 500 MB/s per core.

       zstd command line syntax is generally similar to gzip, but features the
       following differences:

       O   Source files are preserved by default. It's possible to remove them
           automatically by using the --rm command.

       O   When compressing a single file, zstd displays progress notifications
           and result summary by default. Use -q to turn them off.

       O   zstd displays a short help page when command line is an error. Use -q
           to turn it off.

       O   zstd does not accept input from console, though it does accept stdin
           when it's not the console.

       O   zstd does not store the input's filename or attributes, only its

       zstd processes each file according to the selected operation mode. If no
       files are given or file is -, zstd reads from standard input and writes
       the processed data to standard output. zstd will refuse to write
       compressed data to standard output if it is a terminal: it will display
       an error message and skip the file. Similarly, zstd will refuse to read
       compressed data from standard input if it is a terminal.

       Unless --stdout or -o is specified, files are written to a new file whose
       name is derived from the source file name:

       O   When compressing, the suffix .zst is appended to the source filename
           to get the target filename.

       O   When decompressing, the .zst suffix is removed from the source
           filename to get the target filename

   Concatenation with .zst Files
       It is possible to concatenate multiple .zst files. zstd will decompress
       such agglomerated file as if it was a single .zst file.


   Integer Suffixes and Special Values
       In most places where an integer argument is expected, an optional suffix
       is supported to easily indicate large integers. There must be no space
       between the integer and the suffix.

       KiB    Multiply the integer by 1,024 (2\^10). Ki, K, and KB are accepted
              as synonyms for KiB.

       MiB    Multiply the integer by 1,048,576 (2\^20). Mi, M, and MB are
              accepted as synonyms for MiB.

   Operation Mode
       If multiple operation mode options are given, the last one takes effect.

       -z, --compress
              Compress. This is the default operation mode when no operation
              mode option is specified and no other operation mode is implied
              from the command name (for example, unzstd implies --decompress).

       -d, --decompress, --uncompress

       -t, --test
              Test the integrity of compressed files. This option is equivalent
              to --decompress --stdout > /dev/null, decompressed data is
              discarded and checksummed for errors. No files are created or

       -b#    Benchmark file(s) using compression level #. See BENCHMARK below
              for a description of this operation.

       --train FILES
              Use FILES as a training set to create a dictionary. The training
              set should contain a lot of small files (> 100). See DICTIONARY
              BUILDER below for a description of this operation.

       -l, --list
              Display information related to a zstd compressed file, such as
              size, ratio, and checksum. Some of these fields may not be
              available. This command's output can be augmented with the -v

   Operation Modifiers
       O   -#: selects # compression level [1-19] (default: 3)

       O   --ultra: unlocks high compression levels 20+ (maximum 22), using a
           lot more memory. Note that decompression will also require more
           memory when using these levels.

       O   --fast[=#]: switch to ultra-fast compression levels. If =# is not
           present, it defaults to 1. The higher the value, the faster the
           compression speed, at the cost of some compression ratio. This
           setting overwrites compression level if one was set previously.
           Similarly, if a compression level is set after --fast, it overrides

       O   -T#, --threads=#: Compress using # working threads (default: 1). If #
           is 0, attempt to detect and use the number of physical CPU cores. In
           all cases, the nb of threads is capped to ZSTDMT_NBWORKERS_MAX, which
           is either 64 in 32-bit mode, or 256 for 64-bit environments. This
           modifier does nothing if zstd is compiled without multithread

       O   --single-thread: Use a single thread for both I/O and compression. As
           compression is serialized with I/O, this can be slightly slower.
           Single-thread mode features significantly lower memory usage, which
           can be useful for systems with limited amount of memory, such as
           32-bit systems.

           Note 1: this mode is the only available one when multithread support
           is disabled.

           Note 2: this mode is different from -T1, which spawns 1 compression
           thread in parallel with I/O. Final compressed result is also slightly
           different from -T1.

       O   --auto-threads={physical,logical} (default: physical): When using a
           default amount of threads via -T0, choose the default based on the
           number of detected physical or logical cores.

       O   --adapt[=min=#,max=#]: zstd will dynamically adapt compression level
           to perceived I/O conditions. Compression level adaptation can be
           observed live by using command -v. Adaptation can be constrained
           between supplied min and max levels. The feature works when combined
           with multi-threading and --long mode. It does not work with
           --single-thread. It sets window size to 8 MiB by default (can be
           changed manually, see wlog). Due to the chaotic nature of dynamic
           adaptation, compressed result is not reproducible.

           Note: at the time of this writing, --adapt can remain stuck at low
           speed when combined with multiple worker threads (>=2).

       O   --long[=#]: enables long distance matching with # windowLog, if # is
           not present it defaults to 27. This increases the window size
           (windowLog) and memory usage for both the compressor and
           decompressor. This setting is designed to improve the compression
           ratio for files with long matches at a large distance.

           Note: If windowLog is set to larger than 27, --long=windowLog or
           --memory=windowSize needs to be passed to the decompressor.

       O   -D DICT: use DICT as Dictionary to compress or decompress FILE(s)

       O   --patch-from FILE: Specify the file to be used as a reference point
           for zstd's diff engine. This is effectively dictionary compression
           with some convenient parameter selection, namely that windowSize >

           Note: cannot use both this and -D together.

           Note: --long mode will be automatically activated if chainLog <
           fileLog (fileLog being the windowLog required to cover the whole
           file). You can also manually force it.

           Note: for all levels, you can use --patch-from in --single-thread
           mode to improve compression ratio at the cost of speed.

           Note: for level 19, you can get increased compression ratio at the
           cost of speed by specifying --zstd=targetLength= to be something
           large (i.e. 4096), and by setting a large --zstd=chainLog=.

       O   --rsyncable: zstd will periodically synchronize the compression state
           to make the compressed file more rsync-friendly. There is a
           negligible impact to compression ratio, and a potential impact to
           compression speed, perceptible at higher speeds, for example when
           combining --rsyncable with many parallel worker threads. This feature
           does not work with --single-thread. You probably don't want to use it
           with long range mode, since it will decrease the effectiveness of the
           synchronization points, but your mileage may vary.

       O   -C, --[no-]check: add integrity check computed from uncompressed data
           (default: enabled)

       O   --[no-]content-size: enable / disable whether or not the original
           size of the file is placed in the header of the compressed file. The
           default option is --content-size (meaning that the original size will
           be placed in the header).

       O   --no-dictID: do not store dictionary ID within frame header
           (dictionary compression). The decoder will have to rely on implicit
           knowledge about which dictionary to use, it won't be able to check if
           it's correct.

       O   -M#, --memory=#: Set a memory usage limit. By default, zstd uses 128
           MiB for decompression as the maximum amount of memory the
           decompressor is allowed to use, but you can override this manually if
           need be in either direction (i.e. you can increase or decrease it).

           This is also used during compression when using with --patch-from=.
           In this case, this parameter overrides that maximum size allowed for
           a dictionary. (128 MiB).

           Additionally, this can be used to limit memory for dictionary
           training. This parameter overrides the default limit of 2 GiB. zstd
           will load training samples up to the memory limit and ignore the

       O   --stream-size=#: Sets the pledged source size of input coming from a
           stream. This value must be exact, as it will be included in the
           produced frame header. Incorrect stream sizes will cause an error.
           This information will be used to better optimize compression
           parameters, resulting in better and potentially faster compression,
           especially for smaller source sizes.

       O   --size-hint=#: When handling input from a stream, zstd must guess how
           large the source size will be when optimizing compression parameters.
           If the stream size is relatively small, this guess may be a poor one,
           resulting in a higher compression ratio than expected. This feature
           allows for controlling the guess when needed. Exact guesses result in
           better compression ratios. Overestimates result in slightly degraded
           compression ratios, while underestimates may result in significant

       O   -o FILE: save result into FILE.

       O   -f, --force: disable input and output checks. Allows overwriting
           existing files, input from console, output to stdout, operating on
           links, block devices, etc. During decompression and when the output
           destination is stdout, pass-through unrecognized formats as-is.

       O   -c, --stdout: write to standard output (even if it is the console);
           keep original files unchanged.

       O   --[no-]sparse: enable / disable sparse FS support, to make files with
           many zeroes smaller on disk. Creating sparse files may save disk
           space and speed up decompression by reducing the amount of disk I/O.
           default: enabled when output is into a file, and disabled when output
           is stdout. This setting overrides default and can force sparse mode
           over stdout.

       O   --[no-]pass-through enable / disable passing through uncompressed
           files as-is. During decompression when pass-through is enabled,
           unrecognized formats will be copied as-is from the input to the
           output. By default, pass-through will occur when the output
           destination is stdout and the force (-f) option is set.

       O   --rm: remove source file(s) after successful compression or
           decompression. This command is silently ignored if output is stdout.
           If used in combination with -o, triggers a confirmation prompt (which
           can be silenced with -f), as this is a destructive operation.

       O   -k, --keep: keep source file(s) after successful compression or
           decompression. This is the default behavior.

       O   -r: operate recursively on directories. It selects all files in the
           named directory and all its subdirectories. This can be useful both
           to reduce command line typing, and to circumvent shell expansion
           limitations, when there are a lot of files and naming breaks the
           maximum size of a command line.

       O   --filelist FILE read a list of files to process as content from FILE.
           Format is compatible with ls output, with one file per line.

       O   --output-dir-flat DIR: resulting files are stored into target DIR
           directory, instead of same directory as origin file. Be aware that
           this command can introduce name collision issues, if multiple files,
           from different directories, end up having the same name. Collision
           resolution ensures first file with a given name will be present in
           DIR, while in combination with -f, the last file will be present

       O   --output-dir-mirror DIR: similar to --output-dir-flat, the output
           files are stored underneath target DIR directory, but this option
           will replicate input directory hierarchy into output DIR.

           If input directory contains "..", the files in this directory will be
           ignored. If input directory is an absolute directory (i.e.
           "/var/tmp/abc"), it will be stored into the "output-dir/var/tmp/abc".
           If there are multiple input files or directories, name collision
           resolution will follow the same rules as --output-dir-flat.

       O   --format=FORMAT: compress and decompress in other formats. If
           compiled with support, zstd can compress to or decompress from other
           compression algorithm formats. Possibly available options are zstd,
           gzip, xz, lzma, and lz4. If no such format is provided, zstd is the

       O   -h/-H, --help: display help/long help and exit

       O   -V, --version: display version number and exit. Advanced: -vV also
           displays supported formats. -vvV also displays POSIX support. -q will
           only display the version number, suitable for machine reading.

       O   -v, --verbose: verbose mode, display more information

       O   -q, --quiet: suppress warnings, interactivity, and notifications.
           specify twice to suppress errors too.

       O   --no-progress: do not display the progress bar, but keep all other

       O   --show-default-cparams: shows the default compression parameters that
           will be used for a particular input file, based on the provided
           compression level and the input size. If the provided file is not a
           regular file (e.g. a pipe), this flag will output the parameters used
           for inputs of unknown size.

       O   --: All arguments after -- are treated as files

   gzip Operation Modifiers
       When invoked via a gzip symlink, zstd will support further options that
       intend to mimic the gzip behavior:

       -n, --no-name
              do not store the original filename and timestamps when compressing
              a file. This is the default behavior and hence a no-op.

       --best alias to the option -9.

   Environment Variables
       Employing environment variables to set parameters has security
       implications. Therefore, this avenue is intentionally limited. Only
       ZSTD_CLEVEL and ZSTD_NBTHREADS are currently supported. They set the
       compression level and number of threads to use during compression,

       ZSTD_CLEVEL can be used to set the level between 1 and 19 (the "normal"
       range). If the value of ZSTD_CLEVEL is not a valid integer, it will be
       ignored with a warning message. ZSTD_CLEVEL just replaces the default
       compression level (3).

       ZSTD_NBTHREADS can be used to set the number of threads zstd will attempt
       to use during compression. If the value of ZSTD_NBTHREADS is not a valid
       unsigned integer, it will be ignored with a warning message.
       ZSTD_NBTHREADS has a default value of (1), and is capped at
       ZSTDMT_NBWORKERS_MAX==200. zstd must be compiled with multithread support
       for this to have any effect.

       They can both be overridden by corresponding command line arguments: -#
       for compression level and -T# for number of compression threads.


       zstd offers dictionary compression, which greatly improves efficiency on
       small files and messages. It's possible to train zstd with a set of
       samples, the result of which is saved into a file called a dictionary.
       Then, during compression and decompression, reference the same
       dictionary, using command -D dictionaryFileName. Compression of small
       files similar to the sample set will be greatly improved.

       --train FILEs
              Use FILEs as training set to create a dictionary. The training set
              should ideally contain a lot of samples (> 100), and weight
              typically 100x the target dictionary size (for example, ~10 MB for
              a 100 KB dictionary). --train can be combined with -r to indicate
              a directory rather than listing all the files, which can be useful
              to circumvent shell expansion limits.

              Since dictionary compression is mostly effective for small files,
              the expectation is that the training set will only contain small
              files. In the case where some samples happen to be large, only the
              first 128 KiB of these samples will be used for training.

              --train supports multithreading if zstd is compiled with threading
              support (default). Additional advanced parameters can be specified
              with --train-fastcover. The legacy dictionary builder can be
              accessed with --train-legacy. The slower cover dictionary builder
              can be accessed with --train-cover. Default --train is equivalent
              to --train-fastcover=d=8,steps=4.

       -o FILE
              Dictionary saved into FILE (default name: dictionary).

              Limit dictionary to specified size (default: 112640 bytes). As
              usual, quantities are expressed in bytes by default, and it's
              possible to employ suffixes (like KB or MB) to specify larger

       -#     Use # compression level during training (optional). Will generate
              statistics more tuned for selected compression level, resulting in
              a small compression ratio improvement for this level.

       -B#    Split input files into blocks of size # (default: no split)

       -M#, --memory=#
              Limit the amount of sample data loaded for training (default: 2
              GB). Note that the default (2 GB) is also the maximum. This
              parameter can be useful in situations where the training set size
              is not well controlled and could be potentially very large. Since
              speed of the training process is directly correlated to the size
              of the training sample set, a smaller sample set leads to faster

              In situations where the training set is larger than maximum
              memory, the CLI will randomly select samples among the available
              ones, up to the maximum allowed memory budget. This is meant to
              improve dictionary relevance by mitigating the potential impact of
              clustering, such as selecting only files from the beginning of a
              list sorted by modification date, or sorted by alphabetical order.
              The randomization process is deterministic, so training of the
              same list of files with the same parameters will lead to the
              creation of the same dictionary.

              A dictionary ID is a locally unique ID. The decoder will use this
              value to verify it is using the right dictionary. By default, zstd
              will create a 4-bytes random number ID. It's possible to provide
              an explicit number ID instead. It's up to the dictionary manager
              to not assign twice the same ID to 2 different dictionaries. Note
              that short numbers have an advantage: an ID < 256 will only need 1
              byte in the compressed frame header, and an ID < 65536 will only
              need 2 bytes. This compares favorably to 4 bytes default.

              Note that RFC8878 reserves IDs less than 32768 and greater than or
              equal to 2\^31, so they should not be used in public.

              Select parameters for the default dictionary builder algorithm
              named cover. If d is not specified, then it tries d = 6 and d = 8.
              If k is not specified, then it tries steps values in the range
              [50, 2000]. If steps is not specified, then the default value of
              40 is used. If split is not specified or split <= 0, then the
              default value of 100 is used. Requires that d <= k. If shrink flag
              is not used, then the default value for shrinkDict of 0 is used.
              If shrink is not specified, then the default value for
              shrinkDictMaxRegression of 1 is used.

              Selects segments of size k with highest score to put in the
              dictionary. The score of a segment is computed by the sum of the
              frequencies of all the subsegments of size d. Generally d should
              be in the range [6, 8], occasionally up to 16, but the algorithm
              will run faster with d <= 8. Good values for k vary widely based
              on the input data, but a safe range is [2 * d, 2000]. If split is
              100, all input samples are used for both training and testing to
              find optimal d and k to build dictionary. Supports multithreading
              if zstd is compiled with threading support. Having shrink enabled
              takes a truncated dictionary of minimum size and doubles in size
              until compression ratio of the truncated dictionary is at most
              shrinkDictMaxRegression% worse than the compression ratio of the
              largest dictionary.


              zstd --train-cover FILEs

              zstd --train-cover=k=50,d=8 FILEs

              zstd --train-cover=d=8,steps=500 FILEs

              zstd --train-cover=k=50 FILEs

              zstd --train-cover=k=50,split=60 FILEs

              zstd --train-cover=shrink FILEs

              zstd --train-cover=shrink=2 FILEs

              Same as cover but with extra parameters f and accel and different
              default value of split If split is not specified, then it tries
              split = 75. If f is not specified, then it tries f = 20. Requires
              that 0 < f < 32. If accel is not specified, then it tries accel =
              1. Requires that 0 < accel <= 10. Requires that d = 6 or d = 8.

              f is log of size of array that keeps track of frequency of
              subsegments of size d. The subsegment is hashed to an index in the
              range [0,2^f - 1]. It is possible that 2 different subsegments are
              hashed to the same index, and they are considered as the same
              subsegment when computing frequency. Using a higher f reduces
              collision but takes longer.


              zstd --train-fastcover FILEs

              zstd --train-fastcover=d=8,f=15,accel=2 FILEs

              Use legacy dictionary builder algorithm with the given dictionary
              selectivity (default: 9). The smaller the selectivity value, the
              denser the dictionary, improving its efficiency but reducing its
              achievable maximum size. --train-legacy=s=# is also accepted.


              zstd --train-legacy FILEs

              zstd --train-legacy=selectivity=8 FILEs


       -b#    benchmark file(s) using compression level #

       -e#    benchmark file(s) using multiple compression levels, from -b# to
              -e# (inclusive)

       -i#    minimum evaluation time, in seconds (default: 3s), benchmark mode

       -B#, --block-size=#
              cut file(s) into independent chunks of size # (default: no

              set process priority to real-time

       Output Format: CompressionLevel#Filename: InputSize -> OutputSize
       (CompressionRatio), CompressionSpeed, DecompressionSpeed

       Methodology: For both compression and decompression speed, the entire
       input is compressed/decompressed in-memory to measure speed. A run lasts
       at least 1 sec, so when files are small, they are compressed/decompressed
       several times per run, in order to improve measurement accuracy.


       ### -B#: Specify the size of each compression job. This parameter is only
       available when multi-threading is enabled. Each compression job is run in
       parallel, so this value indirectly impacts the nb of active threads.
       Default job size varies depending on compression level (generally 4 *
       windowSize). -B# makes it possible to manually select a custom size. Note
       that job size must respect a minimum value which is enforced
       transparently. This minimum is either 512 KB, or overlapSize, whichever
       is largest. Different job sizes will lead to non-identical compressed

       zstd provides 22 predefined regular compression levels plus the fast
       levels. This compression level is translated internally into a number of
       specific parameters that actually control the behavior of the compressor.
       (You can see the result of this translation with --show-default-cparams.)
       These specific parameters can be overridden with advanced compression
       options. The options are provided as a comma-separated list. You may
       specify only the options you want to change and the rest will be taken
       from the selected or default compression level. The list of available

       strategy=strat, strat=strat
              Specify a strategy used by a match finder.

              There are 9 strategies numbered from 1 to 9, from fastest to
              strongest: 1=ZSTD_fast, 2=ZSTD_dfast, 3=ZSTD_greedy, 4=ZSTD_lazy,
              5=ZSTD_lazy2, 6=ZSTD_btlazy2, 7=ZSTD_btopt, 8=ZSTD_btultra,

       windowLog=wlog, wlog=wlog
              Specify the maximum number of bits for a match distance.

              The higher number of increases the chance to find a match which
              usually improves compression ratio. It also increases memory
              requirements for the compressor and decompressor. The minimum wlog
              is 10 (1 KiB) and the maximum is 30 (1 GiB) on 32-bit platforms
              and 31 (2 GiB) on 64-bit platforms.

              Note: If windowLog is set to larger than 27, --long=windowLog or
              --memory=windowSize needs to be passed to the decompressor.

       hashLog=hlog, hlog=hlog
              Specify the maximum number of bits for a hash table.

              Bigger hash tables cause fewer collisions which usually makes
              compression faster, but requires more memory during compression.

              The minimum hlog is 6 (64 entries / 256 B) and the maximum is 30
              (1B entries / 4 GiB).

       chainLog=clog, clog=clog
              Specify the maximum number of bits for the secondary search
              structure, whose form depends on the selected strategy.

              Higher numbers of bits increases the chance to find a match which
              usually improves compression ratio. It also slows down compression
              speed and increases memory requirements for compression. This
              option is ignored for the ZSTD_fast strategy, which only has the
              primary hash table.

              The minimum clog is 6 (64 entries / 256 B) and the maximum is 29
              (512M entries / 2 GiB) on 32-bit platforms and 30 (1B entries / 4
              GiB) on 64-bit platforms.

       searchLog=slog, slog=slog
              Specify the maximum number of searches in a hash chain or a binary
              tree using logarithmic scale.

              More searches increases the chance to find a match which usually
              increases compression ratio but decreases compression speed.

              The minimum slog is 1 and the maximum is 'windowLog' - 1.

       minMatch=mml, mml=mml
              Specify the minimum searched length of a match in a hash table.

              Larger search lengths usually decrease compression ratio but
              improve decompression speed.

              The minimum mml is 3 and the maximum is 7.

       targetLength=tlen, tlen=tlen
              The impact of this field vary depending on selected strategy.

              For ZSTD_btopt, ZSTD_btultra and ZSTD_btultra2, it specifies the
              minimum match length that causes match finder to stop searching. A
              larger targetLength usually improves compression ratio but
              decreases compression speed.

              For ZSTD_fast, it triggers ultra-fast mode when > 0. The value
              represents the amount of data skipped between match sampling.
              Impact is reversed: a larger targetLength increases compression
              speed but decreases compression ratio.

              For all other strategies, this field has no impact.

              The minimum tlen is 0 and the maximum is 128 KiB.

       overlapLog=ovlog, ovlog=ovlog
              Determine overlapSize, amount of data reloaded from previous job.
              This parameter is only available when multithreading is enabled.
              Reloading more data improves compression ratio, but decreases

              The minimum ovlog is 0, and the maximum is 9. 1 means "no
              overlap", hence completely independent jobs. 9 means "full
              overlap", meaning up to windowSize is reloaded from previous job.
              Reducing ovlog by 1 reduces the reloaded amount by a factor 2. For
              example, 8 means "windowSize/2", and 6 means "windowSize/8". Value
              0 is special and means "default": ovlog is automatically
              determined by zstd. In which case, ovlog will range from 6 to 9,
              depending on selected strat.

       ldmHashLog=lhlog, lhlog=lhlog
              Specify the maximum size for a hash table used for long distance

              This option is ignored unless long distance matching is enabled.

              Bigger hash tables usually improve compression ratio at the
              expense of more memory during compression and a decrease in
              compression speed.

              The minimum lhlog is 6 and the maximum is 30 (default: 20).

       ldmMinMatch=lmml, lmml=lmml
              Specify the minimum searched length of a match for long distance

              This option is ignored unless long distance matching is enabled.

              Larger/very small values usually decrease compression ratio.

              The minimum lmml is 4 and the maximum is 4096 (default: 64).

       ldmBucketSizeLog=lblog, lblog=lblog
              Specify the size of each bucket for the hash table used for long
              distance matching.

              This option is ignored unless long distance matching is enabled.

              Larger bucket sizes improve collision resolution but decrease
              compression speed.

              The minimum lblog is 1 and the maximum is 8 (default: 3).

       ldmHashRateLog=lhrlog, lhrlog=lhrlog
              Specify the frequency of inserting entries into the long distance
              matching hash table.

              This option is ignored unless long distance matching is enabled.

              Larger values will improve compression speed. Deviating far from
              the default value will likely result in a decrease in compression

              The default value is wlog - lhlog.

       The following parameters sets advanced compression options to something
       similar to predefined level 19 for files bigger than 256 KB:



       zstdgrep(1), zstdless(1), gzip(1), xz(1)

       The zstandard format is specified in Y. Collet, "Zstandard Compression
       and the 'application/zstd' Media Type",, Internet RFC 8878 (February 2021).


       Report bugs at:


       Yann Collet

zstd 1.5.5                         March 2023                            zstd(1)

zstd 1.5.5 - Generated Wed Apr 5 07:35:04 CDT 2023
© 2000-2023
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