Changes for version 0.10 - 2026-11-08
- Since 0.09: Spawner.so loads with perl before 5.34 (X36, RT #182809; thanks to Slaven Rezic for the report); echo, printf, test, [, true and false inside Perl as coreutils 9.4 (X21, partly; IP1, IP2); Windows: win_priority and win_job (W4), SetChildShowWindow, more than 64 children, X34 fixed; on_write gets the errno; X27: the run's environment varied, stand-ins and fixed file times (EV1); the run-time comparison redone and its table replaced (A1(b)); the comparison and the snippet library through Run; X33, X35 fixed. The figures of post4-0.04 hold (the measured files differ only in $VERSION); digest of the code they depend on: 4185f0fc85d210c5d14e02c79c998ea586198496e58b4e1caf7a9154c969f11e.
- X36 (ours; RT #182809, Slaven Rezic: 'Undefined symbol "av_count"', 2026-11-08; thanks to Slaven): since 0.01 Spawner.xs used av_count(), which perl has only since 5.33.1, so with perl 5.30 (and any perl before 5.34, though MIN_PERL_VERSION is 5.020) Spawner.so did not load and every test failed. Spawner.xs defines it where perl does not, as perl does (AvFILL + 1). Checked with perl 5.30.3 built here (Linux): 0.09 fails to load as reported; now the suite passes; the XS also compiles against perl 5.20.3's headers with no undeclared function (that perl itself did not build here, so the suite was not run on it). FreeBSD itself not tested here.
- X21, partly (the user, 2026-11-08: "echo, printf, test", "inside the Perl process"): Proc::ShellSpawn::Programs does echo, printf, test, [, true and false as GNU coreutils 9.4 does them, in Perl (Perl's sprintf and file tests, Math::BigInt for the 64-bit range checks, test's grammar as a recursive descent), with output and messages in the program's order (glibc's error() flushes stdout first) and its write errors (SIGPIPE, "write error"). Decision IP1 (the user: "when a well-debugged builtin is already present, use it. (By default; Configurable.)"): Proc::ShellSpawn runs them inside Perl on every platform; PROC_SHELLSPAWN_INPROC=none runs the programs (or names only some), and %Proc::ShellSpawn::INPROC can be changed. command -v names them where there is no program. Checked against coreutils 9.4 on 12,348 runs (handwritten and generated cases, C and UTF-8 locales) and on 3,000 random words for %q; t/programs.t replays 2,284 recorded runs (also under Wine with Strawberry Perl: pass) and compares the shell layer with the programs and in-process; the suite passes both ways (t/dash.t: 550 commands of the batteries). Differences: --help and --version texts, printf's floating conversions in double (coreutils: long double), and %q, where coreutils 9.4 has a ❰BUG❱ (gnulib's quotearg keeps a stale state when it starts a word over: an extra '', or a missing $' that makes the shell read the word back wrong); ours follows gnulib's fixed rule (decision IP2, the user: "Use the builtin").
- Proc::Spawner::on_write: the callback gets the errno of a failed write (it got nothing); Proc::Spawner::Graph's perl_write passes it in $!.
- W4 (the user, 2026-11-08: "(c) and (b); (c) beats (b) if present"): on Windows, win_priority (a priority class) and win_job (job limits by Windows' names: ProcessMemoryLimit, JobMemoryLimit, PerProcessUserTimeLimit, PerJobUserTimeLimit, ActiveProcessLimit), exact, per child; nice and rlimit mapped to them, approximately (nice to the class with the nearest nice value; AS, DATA, CPU, NPROC to job limits; other resources unsupported); win_* win where both are given, and are unsupported elsewhere. The class is set on the suspended child (Wine ignores it as a creation flag). Checked under Wine with a child printing its class; Wine stores no job limits, so theirs is not checked; the mapping is tested in t/spawner.t.
- Windows (the TODO's work items; checked under Wine with Strawberry Perl 5.38.2): Win32::SetChildShowWindow is honoured as by Perl's own spawn (a child printing its startup info: the same through both primitives); more than 64 children at once work (100 checked: the loop polls each child; Perl's own spawn still stops at 64, its table); Makefile.PL skips the POSIX probes there, and perl Makefile.PL, gmake (no warning) and gmake test of t/windows.t and t/parsers.t pass with Strawberry Perl's own gcc and gmake. nice and rlimit there are decisions (TODO A.12).
- X34 ❰BUG❱ (ours; 0.07 to 0.09, Windows code): the kept process handles were in a fixed table of 1,024, and a child started while it was full lost its status if it ended before it was waited for (76 of 1,100 under Wine); the table grows now (the same check: none lost).
- TODO: two pending decisions added (a missing Run in M2; keeping Perl's reopen of the graph's own pipes).
- X27, the run's environment varied (2026-11-08): the six kinds of workaround (nothing, a second run with the other case, fixtures, chosen values, stand-ins for programs, leaving samples out) listed per code in doc/large-subset/large-subset-environment.md, section 9. large-subset-runcompare.pl -env: posix (POSIXLY_CORRECT=1), utf8, sigpipe (ignored), noproc (/proc hidden), tmp (a fresh tmpfs on /tmp, /var/tmp, /dev/shm per run), random (a fixed file over /dev/urandom), private (empty /home, /root, /mnt, /media, /srv, /var), dev (a private /dev); the mounts in a mount namespace of each run's own. -base (the mounting variants need one outside what they hide), -only @FILE; ours runs from a copy of lib/, blib/, t/try.pl. large-subset-runreport.pl -b BASE (each sample's class against a base run's, and what changed) and -c. Each variant on its code's samples against two base runs (the noise): POSIXLY_CORRECT turns the program echo from bash's side to dash's (29) and makes ours differ from both for \x (2); C.UTF-8 changes one printf "\u20AC"; SIGPIPE ignored changes only messages and 6 timeouts; /proc hidden makes the 3 samples using /dev/stdin, /dev/stderr fail alike; a fresh /tmp makes 6 agree whose shells met each other's files there (or another sample's: /tmp is shared across the whole run); a fixed /dev/urandom makes all 25 agree; private and dev change nothing. Every changed sample: doc/large-subset/tools/ large-subset-env-variants.tsv. The levels are not changed by it (TODO, A1 and A2a). bash 5.2.21 does not emulate /dev/stdin and the like without /proc (the document said it did; corrected).
- X33 (ours, in large-subset-runcompare.pl since post4-0.04): each run's output and error files belonged to root, so /dev/stdout and /dev/stderr, which Linux reopens by path, were not writable for the run's user ("Permission denied" in all three shells; one sample affected in practice, tee /dev/stderr). Fixed: the files are given to the run's user first.
- X27, EV1 (the user, 2026-11-08): the runs with the environment varied are footnotes to the level totals (large-subset-environment.md, section 1; README), not levels.
- X27, stand-ins and fixed file times (the user, 2026-11-08: their answers controlled by the environment): large-subset-runcompare.pl -env fail (every program the run only logs exits with STANDIN_STATUS, default 1), output (prints STANDIN_OUTPUT, default "one two\n*\n\nlast"), mtime (the run's copy of the fixture gets the times FIXTURE_MTIME, default 2020-01-01); the values from the runner's own environment, recorded in OUTDIR/env.txt. Run on the samples of prog-status (113), prog-output (1,014) and time (223) against two base runs: status 1 changes nothing beyond the messages; the chosen output parts dash and bash in 47 samples, none with ours against both (cd and kill given several words, test ==, all decided or known; and X35); fixed times cut the changes between two runs of those samples from 50 to 32 (the rest: the shells' own clocks, times outside the run's copy). large-subset-environment.md, section 9 and footnote 2; large-subset-env-variants.tsv.
- X35 (ours; fixed as dash, the user, 2026-11-08): unset of a word that is not a name (from an expansion; the parser rejects a literal one) did nothing with status 0. Now, as dash, it stops the shell with "unset: WORD: bad variable name" and status 2, the names before it already unset; unset -f takes any word. bash takes such a word for a function's name. 6 strings in t/batteries/largebattery.txt.
- large-subset-runcompare.pl -run RUNLIB: ours goes through Run (as where there is neither posix_spawn nor fork: M2, the primitive system1), PROC_SPAWNER_MISSING="posix_spawn fork" for ours alone; t/try.pl takes the names in TRY_HIDE out of the environment once the modules are loaded, so that the samples do not see it.
- The whole snippet library through Run (the user, 2026-11-08): run twice in the same environment (-env tmp,random,mtime), ours through posix_spawn and ours through Run 0.07 (-run): the tables agree, and sample by sample ours changed in 53, all by timing, process IDs or clocks (49 of them with the shells changing too); no difference comes from Run, so no Run bug to fix. Run's tests and Proc-Spawner's suite through Run (also RUN_AS_WIN32=1) pass. large-subset-state.md, section 7, "Through Run".
- A1(b) (the user, 2026-11-08): the run-time comparison redone with a fresh /tmp, a fixed /dev/urandom and fixed file times (-env tmp,random,mtime) replaces post4-0.04's table: same 15,861 (15,751), messages only 23,311 (23,396), ours differs 3 (7), the shells differ 1,220 (1,239), timeouts 15 (17). The 3: printf -v (2, Q2) and echo into a broken pipe in a subshell (1); of post4-0.04's other 4, printf '%0.s-' now agrees (Z0), /dev/urandom agrees, the other 2 were chance. large-subset-state.md, section 7 (also the external calls), README, large-subset-run-differences.tsv, test-pools.md; the X27 cross-check (large-subset-environment.md, section 5) comes out the same. The atomic-call tables stay those of post4-0.04.
Documentation
a map of the design documents shipped in doc/ (EXPERIMENTAL)
Modules
builtins of the large shell subset: alias, the job builtins, and the interactive ones (EXPERIMENTAL)
echo, printf, test and [ as GNU coreutils 9.4 does them, inside the Perl process (EXPERIMENTAL)
parse a Bourne-shell subset into a tree (EXPERIMENTAL)
parse as much of POSIX sh as dash and bash run alike (EXPERIMENTAL)
the Proc::ShellSubset grammar with its options frozen (EXPERIMENTAL)
start children with posix_spawn(3) and run the one event loop (EXPERIMENTAL)
Provides
in lib/Proc/ShellSpawn.pm
in lib/Proc/ShellSpawn/Large.pm
in lib/Proc/Spawner/Graph.pm