OS Manuals

/usr/lib/jvm/java-1.8-openjdk-openj9/bin/pack200

OpenJDK 8 with OpenJ9

From openjdk-8-openj9 0.61.0-r8 (enterprise-packages), captured 2026-11-08 by running pack200 --help (exit 1). permalink

Usage:  pack200 [-opt... | --option=value]... x.pack[.gz] y.jar

Packing Options
  -g, --no-gzip                   output a plain *.pack file with no zipping
  --gzip                          (default) post-process the pack output with gzip
  -G, --strip-debug               remove debugging attributes while packing
  -O, --no-keep-file-order        do not transmit file ordering information
  --keep-file-order               (default) preserve input file ordering
  -S{N}, --segment-limit={N}      output segment limit (default N=1Mb)
  -E{N}, --effort={N}             packing effort (default N=5)
  -H{h}, --deflate-hint={h}       transmit deflate hint: true, false, or keep (default)
  -m{V}, --modification-time={V}  transmit modtimes: latest or keep (default)
  -P{F}, --pass-file={F}          transmit the given input element(s) uncompressed
  -U{a}, --unknown-attribute={a}  unknown attribute action: error, strip, or pass (default)
  -C{N}={L}, --class-attribute={N}={L}  (user-defined attribute)
  -F{N}={L}, --field-attribute={N}={L}  (user-defined attribute)
  -M{N}={L}, --method-attribute={N}={L} (user-defined attribute)
  -D{N}={L}, --code-attribute={N}={L}   (user-defined attribute)
  -f{F}, --config-file={F}        read file F for Pack200.Packer properties
  -v, --verbose                   increase program verbosity
  -q, --quiet                     set verbosity to lowest level
  -l{F}, --log-file={F}           output to the given log file, or '-' for System.out
  -?, -h, --help                  print this message
  -V, --version                   print program version
  -J{X}                           pass option X to underlying Java VM

Notes:
  The -P, -C, -F, -M, and -D options accumulate.
  Example attribute definition:  -C SourceFile=RUH .
  Config. file properties are defined by the Pack200 API.
  For meaning of -S, -E, -H-, -m, -U values, see Pack200 API.
  Layout definitions (like RUH) are defined by JSR 200.

Repacking mode updates the JAR file with a pack/unpack cycle:
    pack200 [-r|--repack] [-opt | --option=value]... [repackedy.jar] y.jar
Options (23)
OptionDescriptionSource
-g, --no-gzipoutput a plain *.pack file with no zippinghelp + man
--gzip(default) post-process the pack output with gziphelp
-G, --strip-debugStrips debugging attributes from the output.help + man
-O, --no-keep-file-orderThe packer reorders and transmits all elements.help + man
--keep-file-orderPreserve the order of files in the input file.help + man
--segment-limit, -Svalue NThe value is the estimated target size N (in bytes) of each archive segment.help + man
--effort, -Evalue NIf the value is set to a single decimal digit, then the packer uses the indicated amount of effort in compressing the archive.help + man
--deflate-hint, -Hvalue hOverrides the default, which preserves the input information, but can cause the transmitted archive to be larger.help + man
--modification-time, -mvalue Vtransmit modtimes: latest or keep (default)help + man
--pass-file, -Pfile FIndicates that a file should be passed through bytewise with no compression.help + man
--unknown-attribute, -Uaction aOverrides the default behavior, which means that the class file that contains the unknown attribute is passed through with the specified action.help + man
--class-attribute, -Cattribute-name N}={L(user-defined attribute)help + man
--field-attribute, -Fattribute-name N}={L(user-defined attribute)help + man
--code-attribute, -Dattribute-name N}={L(user-defined attribute)help + man
--config-file, -f FA configuration file, containing Java properties to initialize the packer, can be specified on the command line.help + man
-v, --verboseincrease program verbosityhelp + man
-q, --quietSpecifies quiet operation with no messages.help + man
--log-file, -lfilename Foutput to the given log file, or '-' for System.outhelp + man
-?, -h, --helpPrints help information about this command.help + man
-V, --versionPrints version information about this command.help + man
-r, --repackProduces a JAR file by packing and unpacking a JAR file. (in the manual page but not in --help)man
-Mattribute-name, --method-attribute layout (in the manual page but not in --help)man
-JoptionPasses the specified option to the Java Virtual Machine. (in the manual page but not in --help)man
Exit status (1) from the manual page
0an error occurs

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