[PATCH 2/2] Add note about tar file portability.

[Manuel Jacob]

I found the link when doing research for the previous patch. Adding `--pax-option=exthdr.name=%d/PaxHeaders/%f,delete=atime,delete=ctime` automatically sets the pax format, which is less portable than the ustar or GNU formats, so adding this note might be a good idea despite the page being about reproducibility.
---
 _docs/archives.md | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/_docs/archives.md b/_docs/archives.md
index 04385390..81587c1c 100644
--- a/_docs/archives.md
+++ b/_docs/archives.md
@@ -107,7 +107,7 @@ PAX headers
 If GNU tar outputs the pax format (which is the default on some distributions), it adds files' ctime and atime. If, in addition, `POSIXLY_CORRECT` is set, it adds the PID of the tar process.
 
 To avoid this, add to the tar call `--pax-option=exthdr.name=%d/PaxHeaders/%f,delete=atime,delete=ctime` or `--format=gnu` (both only available in GNU tar),
-or use `--format=ustar` if the limitations in that format are not a problem.
+or use `--format=ustar` if the limitations in that format are not a problem. Use the latter if possible and [portability](https://mgorny.pl/articles/portability-of-tar-features.html) is a concern.
 
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2.53.0