I've pushed executable adb file to /system for using it to connect to other devices, but shell can't execute this file. Why?
chiron / # file `which adb`
/system/xbin/adb: ELF executable, 64-bit LSB arm64, dynamic (/lib/ld-linux-aarch64.so.1), BuildID=408e8d3f813fbb95b782db5d56f91bc41b451acb, stripped
chiron / # adb
bash: /system/xbin/adb: No such file or directory
You probably did cross-compilation badly.
As file suggests, the dynamic linker for the binary is /lib/ld-linux-aarch64.so.1, which doesn't exist on Android. Android's linker is located at /system/bin/linker (32-bit) and /system/bin/linker64. You need to specify this path as the dynamic linker when compiling.
You may try symlink-ing the Android dynamic linker to the path revealed by file.
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