DWARF_GET_FDE_N(3)

hey bestie 💖 you just opened DWARF_GET_FDE_N(3) from the Library Functions Manual, and we're folding that manual-name energy right into the intro like a little name tag 🎀. This page is all about grabbing one FDE descriptor out of a whole lineup, and the vibes are very "pick your fave from the group chat" 💅.

✨ NAME ✨

dwarf_get_fde_n — retrieve FDE descriptor 🦋

🦋 LIBRARY 🦋

DWARF Access Library — literally libdwarf, -ldwarf — yes, that's the library, and yes, it's lowkey iconic.

🌈 SYNOPSIS 🌈

#include <libdwarf.h>

int
dwarf_get_fde_n(Dwarf_Fde *fdelist, Dwarf_Unsigned fde_index,
    Dwarf_Fde *ret_fde, Dwarf_Error *err);

💜 DESCRIPTION 💜

Function dwarf_get_fde_n() retrieves an FDE descriptor from an array of FDE descriptors. It's giving "one specific bestie from the squad" ✨.

Here's the cast, no cap:

• fdelist — should point to an array of FDE descriptors, as returned by the functions dwarf_get_fde_list(3) or dwarf_get_fde_list_eh(3). This is the whole friend group 🫶.
• fde_index — specifies the 0-based index of the desired FDE descriptor. Yes, zero-based, so the first one is at 0, periodt 💅.
• ret_fde — should point to a location that will hold the returned FDE descriptor. This is where your chosen fave gets delivered 🎁.
• err — if this argument is not NULL, it will be used to store error information in case of an error. If it is NULL, then that's just how it is, bestie.

tiny vibe check: fdelist and ret_fde are not optional in the pointer department — the error section below literally calls out NULL 😭.

🔥 RETURN VALUES 🔥

Function dwarf_get_fde_n() returns DW_DLV_OK when it succeeds. Slay ✅.

It returns DW_DLV_NO_ENTRY if the FDE descriptor index specified by argument fde_index is out of range. Basically, you asked for a bestie who isn't in this group chat 🙈.

In case of an error, it returns DW_DLV_ERROR and sets the argument err. So the error info lands in err when you gave it somewhere to go 💀.

🌸 ERRORS 🌸

Function dwarf_get_fde_n() can fail with:

• [DW_DLE_ARGUMENT] — Either of the arguments fdelist or ret_fde was NULL.
• [DW_DLE_NO_ENTRY] — The FDE descriptor index specified by argument fde_index was out of range.

👑 SEE ALSO 👑

The whole recommended-reading squad, all present and accounted for 💖:

• dwarf(3)
• dwarf_get_cie_of_fde(3)
• dwarf_get_fde_at_pc(3)
• dwarf_get_fde_info_for_all_regs(3)
• dwarf_get_fde_info_for_all_regs3(3)
• dwarf_get_fde_info_for_cfa_reg3(3)
• dwarf_get_fde_info_for_reg(3)
• dwarf_get_fde_info_for_reg3(3)
• dwarf_get_fde_instr_bytes(3)
• dwarf_get_fde_list(3)
• dwarf_get_fde_list_eh(3)
• dwarf_get_fde_range(3)

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okay bye bestie 🫶 this page's footer energy is Debian, May 14, 2011, and DWARF_GET_FDE_N(3) — so that's the source/version and date folded into this cute little sign-off instead of copied as a boring last line 💌✨.