build_id_parse_file(9)

build_id_parse_file(9) 💅

okay bestie, welcome to the Kernel API Manual — today's main character is build_id_parse_file(9), and she is here to parse the build ID of an ELF file. no cap, let's get into it ✨

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🎀 NAME 🎀

build_id_parse_file — Parse build ID of ELF file 🦋

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✨ SYNOPSIS ✨

int build_id_parse_file (struct file *file , unsigned char *build_id ,
       __u32 *size );

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🫶 ARGUMENTS 🫶

• file — file object
• build_id — buffer to store build id, at least BUILD_ID_SIZE long
• size — returns actual build id size in case of success

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💜 DESCRIPTION 💜

So here's the vibe check: this function assumes faultable context and can cause page faults to bring in file data into page cache. lowkey important, highkey worth knowing 😭

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⭐ RETURN ⭐

0 on success; negative error, otherwise. periodt 💅

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🌈 SEE ALSO 🌈

• Kernel file ./lib/buildid.c
• build_id_parse_nofault(9)
• build_id_parse(9)
• build_id_parse_buf(9)
• init_vmlinux_build_id(9)

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mwah 💋 this little page is from source/version ./lib, dated October 2026, and it ate fr fr 🎀✨