fdt_del_mem_rsv(9)

💅 fdt_del_mem_rsv — remove a memory reserve map entry ✨

okay so this is a page straight out of the Kernel API Manual, section 9, and bestie it is so much more chill than it sounds. we're deleting one (1) single entry from a device tree blob's memory reserve map. that's it. that's the whole vibe. 🎀

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🌸 NAME 🌸

fdt_del_mem_rsv — remove a memory reserve map entry 🗑️

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✨ SYNOPSIS ✨

int fdt_del_mem_rsv (void *fdt , int n );

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🦋 ARGUMENTS 🦋

• fdt — pointer to the device tree blob. yes queen, the blob itself, hand it over 🫶
• n — the entry to remove. which one? that one. the n-th one. 🔢

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💖 DESCRIPTION 💖

so fdt_del_mem_rsv removes the n-th memory reserve map entry from the blob. slay. one entry, gone, bye. ✌️

⚠️ but listen — this function will delete data from the reservation table, and that means it will therefore change the indexes of some entries in the table. like, the entries after the one you nuked all shift up and their indexes are not what they used to be. do not come for me when your index math breaks. you've been warned, i love you 💀

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👑 RETURN 👑

• 0 — on success, we ate 💅
• -FDT_ERR_NOTFOUND — there is no entry of the given index (i.e. there are less than n+1 reserve map entries). she's not there, bestie 😭
• -FDT_ERR_BADMAGIC
• -FDT_ERR_BADVERSION
• -FDT_ERR_BADSTATE
• -FDT_ERR_BADSTRUCTURE
• -FDT_ERR_BADLAYOUT
• -FDT_ERR_TRUNCATED

those last seven are all just chilling under standard meanings, iykyk 🌈

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🧚 SEE ALSO 🧚

first up, the source home: Kernel file ./scripts/dtc/libfdt/libfdt.h — that's where she lives 🏠

and now, the entire squad, in order, nobody gets left out, i checked twice:

fdt_offset_ptr(9), fdt_next_tag(9), fdt_first_subnode(9), fdt_next_subnode(9), fdt_for_each_subnode(9), fdt_header_size(9), fdt_header_size_(9), fdt_check_header(9), fdt_move(9), fdt_check_full(9), fdt_get_string(9), fdt_string(9), fdt_find_max_phandle(9), fdt_get_max_phandle(9), fdt_generate_phandle(9), fdt_num_mem_rsv(9), fdt_get_mem_rsv(9), fdt_subnode_offset_namelen(9), fdt_subnode_offset(9), fdt_path_offset_namelen(9), fdt_path_offset(9), fdt_get_name(9), fdt_first_property_offset(9), fdt_next_property_offset(9), fdt_for_each_property_offset(9), fdt_get_property_by_offset(9), fdt_get_property_namelen(9), fdt_get_property(9), fdt_getprop_by_offset(9), fdt_getprop_namelen(9), fdt_getprop(9), fdt_get_phandle(9), fdt_get_alias_namelen(9), fdt_get_alias(9), fdt_get_symbol_namelen(9), fdt_get_symbol(9), fdt_get_path(9), fdt_supernode_atdepth_offset(9), fdt_node_depth(9), fdt_parent_offset(9), fdt_node_offset_by_prop_value(9), fdt_node_offset_by_phandle(9), fdt_node_check_compatible(9), fdt_node_offset_by_compatible(9), fdt_stringlist_contains(9), fdt_stringlist_count(9), fdt_stringlist_search(9), fdt_stringlist_get(9), FDT_MAX_NCELLS(9), fdt_address_cells(9), fdt_size_cells(9), fdt_setprop_inplace_namelen_partial(9), fdt_setprop_inplace(9), fdt_setprop_inplace_u32(9), fdt_setprop_inplace_u64(9), fdt_setprop_inplace_cell(9), fdt_nop_property(9), fdt_nop_node(9), fdt_create_with_flags(9), fdt_create(9), fdt_resize(9), fdt_add_reservemap_entry(9), fdt_finish_reservemap(9), fdt_begin_node(9), fdt_property(9), fdt_property_placeholder(9), fdt_end_node(9), fdt_finish(9), fdt_create_empty_tree(9), fdt_open_into(9), fdt_pack(9), fdt_add_mem_rsv(9), fdt_set_name(9), fdt_setprop_namelen(9), fdt_setprop(9), fdt_setprop_placeholder_namelen(9), fdt_setprop_placeholder(9), fdt_setprop_u32(9), fdt_setprop_u64(9), fdt_setprop_cell(9), fdt_setprop_string(9), fdt_setprop_namelen_string(9), fdt_setprop_empty(9), fdt_appendprop(9), fdt_appendprop_u32(9), fdt_appendprop_u64(9), fdt_appendprop_cell(9), fdt_appendprop_string(9), fdt_appendprop_addrrange(9), fdt_delprop(9), fdt_add_subnode_namelen(9), fdt_add_subnode(9), fdt_del_node(9), fdt_overlay_apply(9), fdt_overlay_target_offset(9), fdt_strerror(9)

like. the whole family tree. iconic behavior honestly 🌳✨

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anyway that's the page!! this one came from ./scripts/dtc/libfdt, dated October 2026, and it's fdt_del_mem_rsv(9) all day every day. go delete an entry (just the one), remember the indexes shift, and drink some water bestie 💜🍓🫶