# Linux Kernel Module Cheat
The perfect emulation setup to study and develop the <<linux-kernel>> v5.9.2, kernel modules, <<qemu-buildroot-setup,QEMU>>, <<gem5-buildroot-setup,gem5>> and x86_64, ARMv7 and ARMv8 <<userland-assembly,userland>> and <<baremetal-setup,baremetal>> assembly, <<c,ANSI C>>, <<cpp,C++>> and <<posix,POSIX>>. <<gdb>> and <<kgdb>> just work. Powered by <<about-the-qemu-buildroot-setup,Buildroot>> and <<about-the-baremetal-setup,crosstool-NG>>. Highly automated. Thoroughly documented. Automated <<test-this-repo,tests>>.

##### 17.8.2.1. seq_file single_open

If you have the entire read output upfront, `single_open` is an even more convenient version of seq_file:

    ./seq_file.sh
    echo $?

Outcome: the test passes:

    0

Sources:

- kernel_modules/seq_file_single_open.c

- rootfs_overlay/lkmc/seq_file_single_open.sh

This example produces a debugfs file that behaves like a file that contains:

    ab
    cd