Output will start with program ID followed by attach type, attach flags and program name.

If effective is specified retrieve effective programs that will execute for events within a cgroup. This includes inherited along with attached ones.

The output is similar to the output of cgroup show/list commands: it starts with absolute cgroup path, followed by program ID, attach type, attach flags and program name.

If effective is specified retrieve effective programs that will execute for events within a cgroup. This includes inherited along with attached ones.

ATTACH_FLAGS can be one of: override if a sub-cgroup installs some bpf program, the program in this cgroup yields to sub-cgroup program; multi if a sub-cgroup installs some bpf program, that cgroup program gets run in addition to the program in this cgroup.

Only one program is allowed to be attached to a cgroup with no attach flags or the override flag. Attaching another program will release old program and attach the new one.

Multiple programs are allowed to be attached to a cgroup with multi. They are executed in FIFO order (those that were attached first, run first).

Non-default ATTACH_FLAGS are supported by kernel version 4.14 and later.

ATTACH_TYPE can be on of: ingress ingress path of the inet socket (since 4.10); egress egress path of the inet socket (since 4.10); sock_create opening of an inet socket (since 4.10); sock_ops various socket operations (since 4.12); device device access (since 4.15); bind4 call to bind(2) for an inet4 socket (since 4.17); bind6 call to bind(2) for an inet6 socket (since 4.17); post_bind4 return from bind(2) for an inet4 socket (since 4.17); post_bind6 return from bind(2) for an inet6 socket (since 4.17); connect4 call to connect(2) for an inet4 socket (since 4.17); connect6 call to connect(2) for an inet6 socket (since 4.17); sendmsg4 call to sendto(2), sendmsg(2), sendmmsg(2) for an unconnected udp4 socket (since 4.18); sendmsg6 call to sendto(2), sendmsg(2), sendmmsg(2) for an unconnected udp6 socket (since 4.18); recvmsg4 call to recvfrom(2), recvmsg(2), recvmmsg(2) for an unconnected udp4 socket (since 5.2); recvmsg6 call to recvfrom(2), recvmsg(2), recvmmsg(2) for an unconnected udp6 socket (since 5.2); sysctl sysctl access (since 5.2); getsockopt call to getsockopt (since 5.3); setsockopt call to setsockopt (since 5.3); getpeername4 call to getpeername(2) for an inet4 socket (since 5.8); getpeername6 call to getpeername(2) for an inet6 socket (since 5.8); getsockname4 call to getsockname(2) for an inet4 socket (since 5.8); getsockname6 call to getsockname(2) for an inet6 socket (since 5.8). sock_release closing an userspace inet socket (since 5.9).