Re: Examples of concurrent coproc usage?
On 4/17/24 8:55 PM, Martin D Kealey wrote: On Wed, 17 Apr 2024, Chet Ramey wrote: On 4/16/24 2:46 AM, Carl Edquist wrote: But the shell is pretty slow when you ask it to shovel data around like this. The 'read' builtin, for instance, cautiously does read(2) calls of a single byte at a time. It has to do it that way to find the delimiter on a non-seekable file descriptor, since it has to leave everything it didn't consume available on stdin. Has anyone tried asking any of the kernel teams (Linux, BSD, or other) to add a new system call such as readln() or readd()? They'd probably point you to an optimized version of getdelim/getline. You're just pushing the work down a layer. -- ``The lyf so short, the craft so long to lerne.'' - Chaucer ``Ars longa, vita brevis'' - Hippocrates Chet Ramey, UTech, CWRUc...@case.eduhttp://tiswww.cwru.edu/~chet/ OpenPGP_signature.asc Description: OpenPGP digital signature
Re: bash parallel build: make[1]: warning: -j16 forced in submake: resetting jobserver mode.
On Sun, 14 Apr 2024 at 01:24, Dmitry Goncharov wrote: > > On Sat, Apr 13, 2024 at 12:41 AM Cedric Blancher > wrote: > > > > Good morning! > > > > Building bash HEAD on Cygwin 3.5.3 and Debian Linux 11 in make > > parallel mode issues a warning, which looks like a Makefile bug: > > $ make -h 16 > > ... > > make[1]: warning: -j16 forced in submake: resetting jobserver mode. > > ... > > Can this be fixed please? > > > It takes a certain makefile setting to cause this warning. > E.g. -j16 can be specified in the makefile on the recipe line like this > > $ ls > lib makefile > $ cat makefile > all:; $(MAKE) -C lib -j4 > $ cat lib/makefile > all:; > $ make -j2 > make -C lib -j4 > make[1]: warning: -j4 forced in submake: resetting jobserver mode. > make[1]: Entering directory > '/home/dgoncharov/src/gmake/test/jobserver_reset/lib' > make[1]: 'all' is up to date. > make[1]: Leaving directory > '/home/dgoncharov/src/gmake/test/jobserver_reset/lib' > $ > > Submake detects that it has its own -j switch and it no longer > participates in the parent make job server. > Instead, the submake will become a master of its own jobserver and run > up to 4 (in this example) jobs, and the parent make keep running its > own job server with up to 2 (in this example) jobs. > This can also be caused by settings in submake env. > See https://www.gnu.org/software/make/manual/html_node/Error-Messages.html. > > You can check what env the submake in question has and which recipe > runs it and see where this setting comes from. We were only using make -j16 all at the bash base dir. That should NOT trigger this warning. Ced -- Cedric Blancher [https://plus.google.com/u/0/+CedricBlancher/] Institute Pasteur
