GETUSER(3)

💅 GETUSER(3) — the Library Functions Manual page, bestie edition ✨

okay so we're in the Library Functions Manual, and today's main characters are getuser and sysname — two little functions that answer the eternal questions: who am I and what machine am I on. iconic behaviour, honestly 🫶

✨ NAME ✨

getuser, sysname — get user or system name 👑 no cap, that's the whole job.

🌸 SYNOPSIS 🌸

#include <u.h>
#include <libc.h>

char*     getuser(void)

char*     sysname(void)

look at that. two char*s, zero arguments, maximum main character energy 💅

🦋 DESCRIPTION 🦋

🎀 getuser

getuser returns a pointer to static data which contains the null-terminated name of the user who owns the current process. so it's not giving you a fresh malloc'd string, it's giving you the string — one shared little home for it, iykyk 💖

how does it find out? it calls getuid(2) and then reads /etc/passwd to find the corresponding name. detective work fr fr 🔍✨

🎀 sysname

sysname returns a pointer to static data which contains the name of the machine on which the current process is running. machine name reveal, slay 🖥️💅

its vibe check order goes like this:

1. it looks first for an environment variable $sysname 🌈
2. if there is no such variable, sysname calls gethostname(2) and truncates the returned name at the first dot ✂️
3. if gethostname fails, sysname returns the default name

and here's the cute little difference from getuser: unlike getuser, sysname caches the string, deriving the host name only once. so it does the work one time and then just chills 😌✨

lowkey worth remembering that both of these hand you pointers to static data — the manpage says so explicitly for each, so don't be out here treating them like fresh private copies 🙈

🌟 SOURCE 🌟

the source files, exactly as listed:

/src/lib9/getuser.c
/src/lib9/sysname.c

and that's the page, bestie 🎀 thanks for reading all the way through, you ate 💖 the manual tag on this one is GETUSER(3), and ngl the page doesn't carry a version or date stamp — the footer's just that same GETUSER(3) tag, so no date to report here. bye bestie, go get that user name 🦋✨💜