This release includes three minor fixes, and also updates the minimum Go version required (in go.mod) from 1.18 to 1.20. The fixes are:

• Generalise handling of /dev/stderr and /dev/stdout in #268
• Save FS when record is read so we use that value when lazily splitting in #269
• Use WaitDelay to ensure system() exits quickly when context is cancelled in #270

Full Changelog: v1.30.1...v1.31.0

This is a bugfix release that includes a fix for empty actions like {}. See #262

This release adds one small new feature and fixes a subtle but long-standing bug:

• The new feature is the -N mode command-line option (and corresponding interp.Config field NewlineOutput) to control newline translation on output. Currently the default is "smart", meaning no translation (-N raw) on Unix/Linux and translate LF to CR LF (-N crlf) on Windows, but you can override the OS-based default with the -N option. Thanks @hymkor for the contribution.
• The bug fix is that previously GoAWK used the Go default of "leftmost-first matching", whereas other AWKs use "leftmost-longest matching". So switch to that using the Regexp.Longest method.

This release also includes a small performance improvement to the postincr/postdecr bytecode by @triallax in #253.

Full Changelog: v1.29.1...v1.30.0

This release only exists to add FreeBSD binaries -- no changes since v1.29.0.

This release adds Unicode chars mode with goawk -c (or by setting Config.Chars to true when using the Go API). The default is bytes mode as it was before (except that printf %c used chars mode by default as of v1.28.0 -- now it only does if chars mode is enabled). Note that this is the same default as mawk, but the opposite of Gawk (which uses gawk -b to switch to bytes mode).

Chars mode applies to index(), length(), match() (including RSTART and RLENGTH), substr(), and printf's %c verb.

For example, as of version v1.29.0, you can do this:

$ goawk 'BEGIN { print length("a"), length("絵") }'
1 3
$ goawk -c 'BEGIN { print length("a"), length("絵") }'
1 1

Full Changelog: v1.28.1...v1.29.0

I forgot to bump up the version number for the v1.28.0 release, so this is a patch release with a single commit to do just that.

See also the release notes for the v1.28.0 release.

NOTE: The original binaries were for the v1.28.0 tag, but had the old v1.27.0 version number in the file names (and in the goawk -version output). I've uploaded corrected v1.28.0 binaries here, but there's also a new v1.28.1 patch release with this fixed.

What's Changed

• Fix evaluation of empty {} and END{} by @benhoyt in #230
• fix: close file in Cover.WriteProfile by @testwill in #232
• Fix number formatting on non-64bit architectures by @guilherme-puida in #235
• Make printf %c work on Unicode codepoints by @oliverkwebb in #236
• Improve error message when missing -H or in BEGIN by @benhoyt in #239
• Add printf %i, %a, %A; Fix %o, %x, %X (they should be unsigned) by @benhoyt in #240
• Make srand() use unix time in seconds, and set seed for next srand() by @benhoyt in #241
• Bump up minimum supported Go version to 1.18, and test on 1.23 by @benhoyt in 7f49055

New Contributors

• @testwill made their first contribution in #232
• @oliverkwebb made their first contribution in #236

Full Changelog: v1.27.0...v1.28.0

What's changed

• Fix wrong precedence of 'expr | getline' expressions by @fioriandrea in #216
• Use C.UTF-8 as locale when invoking external awk program by @guilherme-puida in #226 (first-time contributor)
• New feature: Make redirecting to /dev/stderr work on Windows by @benhoyt in #225

Full Changelog: v1.26.0...v1.27.0

What's Changed

• Fix rare race in pipe-to-command close() result test by @juster in #213
• Fix #190: FS regex [^,]* fails on empty field by @fioriandrea in #214
• Fix issue #79: Incorrect parsing of complex ++ expressions by @fioriandrea in #215
• Allow optional newline between "do {}" and "while" by @benhoyt in #220
• Distinguish between /regexp/ and "regexp" in stringified output by @ypdn in #222

New Contributors

• @ypdn made their first contribution in #222

Full Changelog: v1.25.0...v1.26.0

This release includes several minor changes:

• Build binaries with PGO on Go 1.21. GoAWK on Go 1.21 is about 10% faster than on Go 1.20, and PGO makes it another 5-6% faster.
• Bumps up the minimum supported Go version from 1.15 to 1.16.
• Makes the return value of system() and close() for pipes more closely match Gawk's. Internal refactoring of the input and output stream implementation to make this happen. See issues #203 #204 #205 and thanks @juster!
• Support the \u Unicode string escape that's been added to onetrueawk and Gawk recently. #212