z/OS V1R9.0 UNIX System Services Command ... - Christian Grothoff

pax
pax extended header
regular file that contains the extended header records as data. Therefore, header
block field values should be selected to provide reasonable file access to this
regular file.
A further difference from the USTAR header block is that data blocks for files of
typeflag 1 (the digit one) (hard link) may be included, which means that the size
field may be greater than zero. Archives created by pax -o linkdata shall include
these data blocks with the hard links.
Description
A pax extended header contains values that are inappropriate for the USTAR
header block because of limitations in that format: fields requiring a character
encoding other than that described in the ISO/IEC646:1991 standard, fields
representing file attributes not described in the USTAR header, and fields whose
format or length do not fit the requirements of the USTAR header. The values in an
extended header add attributes to the following file (or files; see the description of
the typeflag g header block) or override values in the following header blocks, as
indicated in the following list of keywords.
An extended header shall consist of one or more records, each constructed as
follows:
"%d %s=%s\n", , ,
The extended header records shall be encoded according to the
ISO/IEC10646-1:2000 standard (UTF-8). The field, , equals sign,
and shown shall be limited to the portable character set, as encoded in
UTF-8. The and fields can be any UTF-8 characters. The
field shall be the decimal length of the extended header record in octets,
including the trailing