I am running this on z/OS and want to copy Unix files from one z/OS image to another.

The tar command is very popular, and works for most people.

The pax command is similar to tar, but It can also save and restore file attributes that cannot be handled by any other format such as: files greater than 8 GB, large UID, and GID values , large time values and z/OS -specific attributes like user audit and auditor audit flags and file format.

You create a file using

pax -o saveext -wf pax_file_name files_to_add

and

pax -ppx -rf pax_file_name

to extract the files.

Thanks to Gwydion Tudur for the pointers about extended attributes.

Using a data set

You can use a data set as an output file for example you specify “//’COLIN.PAX.HTTP2′”

pax -E -f “//’COLIN.PAX.HTTP2′”

This will display the contents of the file, for example if gives

drwxrwxrwx        1 OMVSKERN SYS1           0 Aug  4 10:03 ./                                  
drwxrwxrwx        1 OMVSKERN SYS1           0 Nov 15  2021 ./images/                           
drwxrwxrwx        1 OMVSKERN SYS1           0 Nov 15  2021 ./images/ihs/                       
-rwxrwxrwx  --s-  1 OMVSKERN SYS1         223 Nov 15  2021 ./images/ihs/administration.gif     
                 
-rwxrwxrwx  --s-  1 COLIN    SYS1         373 Jun 17  2023 ./colin.html                        

Using a data set makes it more portable, for example it is a data set, not a file in a Unix file system.

File owners

Within the .pax file the file owner is a name. When the file is unpacked, you can use the -p o option to preserves the user ID and group information. On my system userid OMVSKERN has uid 0, and group SYS1 has gid 0. On my newer z/OS system the file got the uid of COLIN on the new system – not from the old system.

Without the -po option, the files get the uid from the userid executing the pax command.