Re: implicit redirection of background within pipeline

Martin Kealey writes: > The standard is actually a bit vague; under "Compound Commands" it mentions > that "Each redirection will apply to all the commands within the compound > command that do not explicitly override that redirection" but it fails to > mention that this

Re: implicit redirection of background within pipeline

On 13 Jan 2016 8:14 p.m., "Andreas Schwab" wrote: > I don't think so. > http://pubs.opengroup.org/onlinepubs/9699919799/utilities/V3_chap02.html#tag_18_07 > doesn't mention pipelines. That was rather my point. Given that they aren't mentioned, one has to take them as read,

Re: implicit redirection of background within pipeline

Martin Kealey writes: > What do other shells do? Ksh? Dash? Zsh? $ ksh -c 'printf "foo1\nfoo2\n" | { (read x; echo 1: $x) & (read x; echo 2: $x) & }' 1: foo1 2: foo2 $ dash -c 'printf "foo1\nfoo2\n" | { (read x; echo 1: $x) & (read x; echo 2: $x) & }' 1: 2: $ zsh -c

Re: implicit redirection of background within pipeline

Martin Kealey writes: > On 13 Jan 2016 8:14 p.m., "Andreas Schwab" wrote: > >> I don't think so. >> > http://pubs.opengroup.org/onlinepubs/9699919799/utilities/V3_chap02.html#tag_18_07 >> doesn't mention pipelines. > > That was rather my point. Given that they

Re: implicit redirection of background within pipeline

On Wed, 13 Jan 2016, Andreas Schwab wrote: > What does "take them as read" mean? Taking something as read means that the author thought we would understand it without them actually writing it down. Or more prosaically, it means to pretend that they're written there, even though they're not,

Re: implicit redirection of background within pipeline

On Wed, 13 Jan 2016, Chet Ramey wrote: > On 1/13/16 4:08 AM, Andreas Schwab wrote: > > Martin Kealey writes: > > > >> What do other shells do? Ksh? Dash? Zsh? > > > > $ ksh -c 'printf "foo1\nfoo2\n" | { (read x; echo 1: $x) & (read x; echo 2: > > $x) & }' > > 1: foo1 > >

Re: implicit redirection of background within pipeline

On 1/13/16 4:08 AM, Andreas Schwab wrote: > Martin Kealey writes: > >> What do other shells do? Ksh? Dash? Zsh? > > $ ksh -c 'printf "foo1\nfoo2\n" | { (read x; echo 1: $x) & (read x; echo 2: > $x) & }' > 1: foo1 > 2: foo2 I changed bash to behave like this, which I

Re: implicit redirection of background within pipeline

On 1/12/16 7:20 PM, Martin Kealey wrote: > > > On Mon, 11 Jan 2016, Chet Ramey wrote: >> "The standard input for an asynchronous list, before any explicit >> redirections are performed, shall be considered to be assigned to a file >> that has the same properties as /dev/null." > > I thought the

Re: implicit redirection of background within pipeline

On 1/10/16 2:23 AM, Martin D Kealey wrote: > Bash Version: 4.3 > Patch Level: 11 > Release Status: release > > Description: > The first backgrounded element within a pipeline component has its > stdin redirected to /dev/null; this does not apply to the second and > subsequent

Re: implicit redirection of background within pipeline

On Mon, 11 Jan 2016, Chet Ramey wrote: > "The standard input for an asynchronous list, before any explicit > redirections are performed, shall be considered to be assigned to a file > that has the same properties as /dev/null." I thought the (only) point of that to avoid a background job

Re: implicit redirection of background within pipeline

Surely a pipe counts as an explicit redirection? And even if it didn't, the inconsistency between the first and subsequent asynchronous elements is confusing. On 12 Jan 2016 02:41, "Chet Ramey" wrote: > On 1/10/16 12:54 PM, Piotr Grzybowski wrote: > > hey, > > > > I am

Re: implicit redirection of background within pipeline

On 1/11/16 3:37 PM, Chet Ramey wrote: > On 1/11/16 3:29 PM, Martin Kealey wrote: >> Surely a pipe counts as an explicit redirection? > > It doesn't. I should be clear that this is according to what the standard says. The existing code attempts to inhibit this implicit redirection in the

Re: implicit redirection of background within pipeline

On 1/11/16 3:29 PM, Martin Kealey wrote: > Surely a pipe counts as an explicit redirection? It doesn't. > And even if it didn't, the inconsistency between the first and subsequent > asynchronous elements is confusing. Agreed. -- ``The lyf so short, the craft so long to lerne.'' - Chaucer

Re: implicit redirection of background within pipeline

Chet Ramey writes: > On 1/10/16 12:54 PM, Piotr Grzybowski wrote: >> hey, >> >> I am quite sure it happens here (devel branch, at >> 6f82653c5ef09aeeeba4376a1c65ce86c3605c00): >> >> execute_cmd.c +5115: >>if ((cmdflags & CMD_STDIN_REDIR) && >> pipe_in == NO_PIPE &&

Re: implicit redirection of background within pipeline

On 1/10/16 12:54 PM, Piotr Grzybowski wrote: > hey, > > I am quite sure it happens here (devel branch, at > 6f82653c5ef09aeeeba4376a1c65ce86c3605c00): > > execute_cmd.c +5115: >if ((cmdflags & CMD_STDIN_REDIR) && > pipe_in == NO_PIPE && > (stdin_redirects (redirects) == 0)) >

Re: implicit redirection of background within pipeline

On 1/11/16 11:37 AM, Andreas Schwab wrote: > Chet Ramey writes: > >> On 1/10/16 12:54 PM, Piotr Grzybowski wrote: >>> hey, >>> >>> I am quite sure it happens here (devel branch, at >>> 6f82653c5ef09aeeeba4376a1c65ce86c3605c00): >>> >>> execute_cmd.c +5115: >>>if

implicit redirection of background within pipeline

Configuration Information [Automatically generated, do not change]: Machine: x86_64 OS: linux-gnu Compiler: gcc Compilation CFLAGS: -DPROGRAM='bash' -DCONF_HOSTTYPE='x86_64' -DCONF_OSTYPE='linux-gnu' -DCONF_MACHTYPE='x86_64-pc-linux-gnu' -DCONF_VENDOR='pc' -DLOCALEDIR='/usr/share/locale'

Re: implicit redirection of background within pipeline

hey, I am quite sure it happens here (devel branch, at 6f82653c5ef09aeeeba4376a1c65ce86c3605c00): execute_cmd.c +5115: if ((cmdflags & CMD_STDIN_REDIR) && pipe_in == NO_PIPE && (stdin_redirects (redirects) == 0)) async_redirect_stdin (); but after reading the comments some 3.5k