Like when I have an electrician at me house. Says the old way was dumb... but that was fully up to code in 1954.
Time makes fools of us all.
On that point, some heavy machinery took years before adding safety guards (some even required legislation before improving safety)
... AFTER a "tvf[jzx]", I hope
Does -x have some side effect that -t would list for you?
Most tar programs do prevent extracting tarballs containing absolute paths (like '/etc/passwd') and relative paths (like '../../../etc/passwd'), but older tar programs still allow that. And programs written in Go, because of course: https://github.com/golang/go/issues/55356
Overall, if your HDD size is infinite and you're using GNU tar, or another recent tar, you can skip 't' I think before doing a '-C' extraction into some safe directory.
To add absolute paths to an archive, there is "-P" option, and man says it works only for creating archives: "Don't strip leading slashes from filenames when creating archives".
To extract absolute paths from the archive, you need to add the "-C /" option, and although the tool says "tar: Strip leading `/' from member names", it will still extract it in the right place because the paths become relative and -C puts them in the root.
However, if you add "-P" during the extraction (which is not mentioned in man), the "strip leading slashes" information disappears.
So if this message bothers someone, "tar -C / -xPf file.tar" will cleanly extract absolute paths from the archive ;)
char name[100];
So anything that will write an absolute path there, including literally opening it in a text editor and replacing the path by hand because that whole header is just fixed length ASCII with null terminated strings.
(I mean I assume the tar(1) command can do it too but you don't need that, the format is dead simple, if weird.)