Hello, everyone.
In order to avoid an XY problem, I would like to introduce the actual problem first.
I need to run a script each time network changes. Android automatically changes quite a few settings when network changes, and because I need to have some of them set to specific values, I need to tweak them each time something happens.
How would I like to proceed:
There is a sysprop setting that changes each time network changes: sys.radio.cellular.netId.
Naturally, I would like to hook my script to that property change.
Android init system seems to provide such an option: init.rc syntax allows to subscribe to a property change using the
syntax.
Seems easy:
Add a custom_network.rc
Add a file /bin/custom_network.sh:
The above is essentially following this guide: https://android.stackexchange.com/q...run-an-executable-on-boot-and-keep-it-running
So, I created a magisk module, added the files above to the $MODDIR/system/etc/init, and $MODDIR/system/bin directories.
Then I added the following lines to the customize.sh:
However, this does not work. The service custom_network does not appear in the getprop | grep svc list, and cannot be started with setprop ctl.start "custom_network".
Is it true that in order for _any_ custom rc files, the system boot image must be patched?
If yes, is there a manual how to do so?
If no, then what am I doing wrong here?
Furthermore, if patching the boot image cannot be avoided, is there a manual on how to do this with minimal pain?
On the other hand, is there a way to avoid adding a custom init service entirely, and add a network listener by some other means?
In order to avoid an XY problem, I would like to introduce the actual problem first.
I need to run a script each time network changes. Android automatically changes quite a few settings when network changes, and because I need to have some of them set to specific values, I need to tweak them each time something happens.
How would I like to proceed:
There is a sysprop setting that changes each time network changes: sys.radio.cellular.netId.
Naturally, I would like to hook my script to that property change.
Android init system seems to provide such an option: init.rc syntax allows to subscribe to a property change using the
Code:
on property:propname=*Seems easy:
Add a custom_network.rc
Bash:
on property:sys.radio.cellular.netId=*
start custom_network
service custom_network /bin/custom_network.sh
user root
seclabel u:r:magisk:s0
oneshot
Bash:
#/system/bin/sh
echo "TODO"The above is essentially following this guide: https://android.stackexchange.com/q...run-an-executable-on-boot-and-keep-it-running
So, I created a magisk module, added the files above to the $MODDIR/system/etc/init, and $MODDIR/system/bin directories.
Then I added the following lines to the customize.sh:
Bash:
set_perm $MODPATH/system/bin/custom_network.sh 0 0 0755
set_perm $MODPATH/bin/custom_network.sh 0 0 0755
chown 0.0 $MODPATH/system/etc/init/custom_network.rc
chmod 0644 $MODPATH/system/etc/init/custom_network.rc
chcon u:object_r:system_file:s0 $MODPATH/system/etc/init/custom_network.rcHowever, this does not work. The service custom_network does not appear in the getprop | grep svc list, and cannot be started with setprop ctl.start "custom_network".
Is it true that in order for _any_ custom rc files, the system boot image must be patched?
If yes, is there a manual how to do so?
If no, then what am I doing wrong here?
Furthermore, if patching the boot image cannot be avoided, is there a manual on how to do this with minimal pain?
On the other hand, is there a way to avoid adding a custom init service entirely, and add a network listener by some other means?
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