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Libbpf userspace function bpf_map_lookup_elem

0.0.1

Low level wrapper around the BPF_MAP_LOOKUP_ELEM syscall command.

Note

This function is part of the libbpf userspace library, but has the same name as the bpf_map_lookup_elem helper function, which can only be used from an eBPF program.

Definition

int bpf_map_lookup_elem(int fd, const void *key, void *value);

Parameters

  • fd: file descriptor of the map to lookup element in
  • key: pointer to memory containing bytes of the key used for lookup
  • value: pointer to memory in which looked up value will be stored

Return

0, on success; negative error, otherwise

Usage

This function should only be used if you need precise control over the map element lookup process. In most cases the bpf_map__lookup_elem function should be used instead.

Example

Docs could be improved

This part of the docs is incomplete, contributions are very welcome