| Message ID | 20180404180935.15185-3-joerg.krause@embedded.rocks |
|---|---|
| State | Accepted |
| Commit | 6919fc55660eafd1a55c2e8535cc9291c251faf5 |
| Headers | show |
| Series | Add /dev/std{in, out, err} symlinks to inittabs | expand |
>>>>> "Jörg" == Jörg Krause <joerg.krause@embedded.rocks> writes: > Some applications, e.g. bashs process subsitution feature, rely on the > convention of `/dev/fd` being a symbolic link to `/proc/self/fd`. > This symbolic link and his companions `/dev/std*` are created by (e)udev [1], > but not by mdev, resulting in the following error when using the following > expression: > ``` > bash: /dev/fd/62: No such file or directory > ``` > For the sake of simplicity, lets fix this by creating the symlinks in inittab. > It is only really needed if eudev isn't used, but it doesn't really hurt to > create them even if eudev will recreate them afterwards. > Note, that we do not create the symlink `/dev/core` as `/proc/kcore` is > not available on all platforms, e.g. ARM, and the feature is not much > appreciated [2]. > [1] > https://github.com/gentoo/eudev/blob/8943501993322c59a6eb5be456b0d716aafff21e/src/shared/dev-setup.c#L35-L40 > [2] https://lwn.net/Articles/45315/ > Signed-off-by: Jörg Krause <joerg.krause@embedded.rocks> > --- > package/sysvinit/inittab | 6 +++++- > 1 file changed, 5 insertions(+), 1 deletion(-) > diff --git a/package/sysvinit/inittab b/package/sysvinit/inittab > index fad91eae8b..608aabce07 100644 > --- a/package/sysvinit/inittab > +++ b/package/sysvinit/inittab > @@ -9,7 +9,11 @@ si1::sysinit:/bin/mount -o remount,rw / > si2::sysinit:/bin/mkdir -p /dev/pts > si3::sysinit:/bin/mkdir -p /dev/shm > si4::sysinit:/bin/mount -a > -si5::sysinit:/bin/hostname -F /etc/hostname > +si5::sysinit:/bin/ln -sf /proc/self/fd /dev/fd > +si6::sysinit:/bin/ln -sf /proc/self/fd/0 /dev/stdin > +si7::sysinit:/bin/ln -sf /proc/self/fd/1 /dev/stdout > +si8::sysinit:/bin/ln -sf /proc/self/fd/2 /dev/stderr This will fail on static /dev on a readonly rootfs, so I've redirected errors to /dev/null. Committed with that changed, thanks. I have also added a patch adding these symlinks in the default skeleton to handle static /dev on readonly rootfs setups.
>>>>> "Peter" == Peter Korsgaard <peter@korsgaard.com> writes: >>>>> "Jörg" == Jörg Krause <joerg.krause@embedded.rocks> writes: >> Some applications, e.g. bashs process subsitution feature, rely on the >> convention of `/dev/fd` being a symbolic link to `/proc/self/fd`. >> This symbolic link and his companions `/dev/std*` are created by (e)udev [1], >> but not by mdev, resulting in the following error when using the following >> expression: >> ``` >> bash: /dev/fd/62: No such file or directory >> ``` >> For the sake of simplicity, lets fix this by creating the symlinks in inittab. >> It is only really needed if eudev isn't used, but it doesn't really hurt to >> create them even if eudev will recreate them afterwards. >> Note, that we do not create the symlink `/dev/core` as `/proc/kcore` is >> not available on all platforms, e.g. ARM, and the feature is not much >> appreciated [2]. >> [1] >> https://github.com/gentoo/eudev/blob/8943501993322c59a6eb5be456b0d716aafff21e/src/shared/dev-setup.c#L35-L40 >> [2] https://lwn.net/Articles/45315/ >> Signed-off-by: Jörg Krause <joerg.krause@embedded.rocks> >> --- >> package/sysvinit/inittab | 6 +++++- >> 1 file changed, 5 insertions(+), 1 deletion(-) >> diff --git a/package/sysvinit/inittab b/package/sysvinit/inittab >> index fad91eae8b..608aabce07 100644 >> --- a/package/sysvinit/inittab >> +++ b/package/sysvinit/inittab >> @@ -9,7 +9,11 @@ si1::sysinit:/bin/mount -o remount,rw / >> si2::sysinit:/bin/mkdir -p /dev/pts >> si3::sysinit:/bin/mkdir -p /dev/shm >> si4::sysinit:/bin/mount -a >> -si5::sysinit:/bin/hostname -F /etc/hostname >> +si5::sysinit:/bin/ln -sf /proc/self/fd /dev/fd >> +si6::sysinit:/bin/ln -sf /proc/self/fd/0 /dev/stdin >> +si7::sysinit:/bin/ln -sf /proc/self/fd/1 /dev/stdout >> +si8::sysinit:/bin/ln -sf /proc/self/fd/2 /dev/stderr > This will fail on static /dev on a readonly rootfs, so I've redirected > errors to /dev/null. > Committed with that changed, thanks. > I have also added a patch adding these symlinks in the default skeleton > to handle static /dev on readonly rootfs setups. Committed to 2018.02.x, thanks.
diff --git a/package/sysvinit/inittab b/package/sysvinit/inittab index fad91eae8b..608aabce07 100644 --- a/package/sysvinit/inittab +++ b/package/sysvinit/inittab @@ -9,7 +9,11 @@ si1::sysinit:/bin/mount -o remount,rw / si2::sysinit:/bin/mkdir -p /dev/pts si3::sysinit:/bin/mkdir -p /dev/shm si4::sysinit:/bin/mount -a -si5::sysinit:/bin/hostname -F /etc/hostname +si5::sysinit:/bin/ln -sf /proc/self/fd /dev/fd +si6::sysinit:/bin/ln -sf /proc/self/fd/0 /dev/stdin +si7::sysinit:/bin/ln -sf /proc/self/fd/1 /dev/stdout +si8::sysinit:/bin/ln -sf /proc/self/fd/2 /dev/stderr +si9::sysinit:/bin/hostname -F /etc/hostname rcS:12345:wait:/etc/init.d/rcS # S0:1:respawn:/sbin/getty -L ttyS0 115200 vt100 # GENERIC_SERIAL
Some applications, e.g. bashs process subsitution feature, rely on the convention of `/dev/fd` being a symbolic link to `/proc/self/fd`. This symbolic link and his companions `/dev/std*` are created by (e)udev [1], but not by mdev, resulting in the following error when using the following expression: ``` bash: /dev/fd/62: No such file or directory ``` For the sake of simplicity, lets fix this by creating the symlinks in inittab. It is only really needed if eudev isn't used, but it doesn't really hurt to create them even if eudev will recreate them afterwards. Note, that we do not create the symlink `/dev/core` as `/proc/kcore` is not available on all platforms, e.g. ARM, and the feature is not much appreciated [2]. [1] https://github.com/gentoo/eudev/blob/8943501993322c59a6eb5be456b0d716aafff21e/src/shared/dev-setup.c#L35-L40 [2] https://lwn.net/Articles/45315/ Signed-off-by: Jörg Krause <joerg.krause@embedded.rocks> --- package/sysvinit/inittab | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-)