- Update to grep 2.27
* grep no longer reports a false match in a multibyte, non-UTF8 locale
like zh_CN.gb18030, with a regular expression like ".*7" that just
happens to match the 4-byte representation of gb18030's \uC9, the
final byte of which is the digit "7".
* grep by default now reads all of standard input if it is a pipe,
even if this cannot affect grep's output or exit status.
* grep no longer mishandles ranges in nontrivial unibyte locales.
* grep -P no longer attempts multiline matches.
* grep -m0 -L PAT FILE now outputs "FILE".
* To output ':' and tab-align the following character C, grep -T no
longer outputs tab-backspace-':'-C, an approach that has problems if
run inside an Emacs shell window.
* grep -T now uses worst-case widths of line numbers and byte offsets
instead of guessing widths that might not work with larger files.
* grep no longer reads the input in a few more cases when it is easy to
see that matching cannot succeed, e.g., 'grep -f /dev/null'. (forwarded request 444685 from Andreas_Schwab)