FUNCTION::USER_STRING_N_WARN(3stap)

💖 FUNCTION::USER_STRING_N_WARN 💖 (3stap)

okay bestie, welcome to the SystemTap Tapset Reference, section 3stap, and today's main character is function::user_string_n_warn. she's a tapset function, she pulls strings out of user space, and she will tell you when things go sideways instead of just ghosting you. 🫶

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✨ NAME ✨

function::user_string_n_warn — Retrieves string from user space 🌸

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🦋 SYNOPSIS 🦋

1) user_string_n_warn:string(addr:long,n:long)

2) user_string_n_warn:string(addr:long,n:long,warn_msg:string)

two whole forms, pick your fighter 💅

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🎀 ARGUMENTS 🎀

• addr — the user space address you're tryna retrieve the string from 👀
• n — the maximum length of the string, for when it's not null terminated (iykyk, strings be like that)
• warn_msg — the warning message she hands back to you when the data just isn't available 😭

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🌈 DESCRIPTION 🌈

1) Returns up to n characters of a C string from a given user space memory address. On the rare cases when userspace data isn't accessible, she reports "<unknown>" — and yes, she warns about the failure (but does not abort, she's dramatic not destructive). 💀

2) Same deal, but glow-up edition: returns up to n characters of a C string from a given user space memory address, and when that userspace data isn't accessible on those rare occasions, she reports the warning message you gave her instead. And yeah — she warns (but does not abort) about the failure. no cap, she just tells you and keeps it moving. ✨

lowkey the whole point: she never crashes your party, she just announces that the data was missing. iconic behaviour fr fr. 👑

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👑 SEE ALSO 👑

• tapset::uconversions(3stap)

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and that's the whole page bestie, go forth and retrieve those strings responsibly 🧚

mwah 💖 this was the SystemTap Tapset Reference (that footer said Ver and everything, it's giving September 2026), so like… see you in the next tapset, periodt. 🎀✨