MEMINS(3pub)

💖 MEMINS(3pub) — the publib glow-up edition ✨

okay bestie, welcome to the C Programmer's Manual, publib chapter, and today's main character is memins 💅 she's a memory-block girly and she EATS.

🌸 NAME 🌸

memins — insert bytes at the beginning of a memory block 🫶

✨ SYNOPSIS ✨

#include <publib.h>
void *memins(void *tgt, size_t tgtsize, const void *src, size_t srcsize);

like. that's the whole vibe. one function, four args, no notes 💀

💜 DESCRIPTION 💜

so here's the tea ☕ memins takes srcsize bytes from src and inserts them at the beginning of tgt — but bestie, she's polite about it, she moves the first tgtsize bytes out of the way to make room 🎀

⚠️ and this is the part where you LISTEN: the source and target memory blocks must not overlap. fr fr. no cap. overlapping them is not it 🙈

🌈 RETURN VALUE 🌈

memins returns its first argument. that's it. that's the whole return. she gives you back tgt like "here u go queen 👑"

🦋 EXAMPLE 🦋

say you wanna insert a new element at the ith position of an array — iconic behavior, very demure. you'd do this:

int new, array[10];

memins(array+i, (10-i-1)*sizeof(array[0]), &new, sizeof(new));

and pls pls PLS notice 👀 that the code above carefully avoids the trap of moving the last element of the array past the end of the array. like, that's the whole reason for the (10-i-1) math bestie, don't skip it, it's giving attention to detail 💅✨

🎀 SEE ALSO 🎀

• publib(3)
• strins(3)

⭐ AUTHOR ⭐

Lars Wirzenius (lars.wirzenius@helsinki.fi) — the legend, the blueprint, the moment 🌟

okay that's the whole page, love u, go forth and insert responsibly 🫶💖 this was publib's C Programmer's Manual, page MEMINS(3pub), brought to you by the publib girlies ✨ bye bestie!! 🎀🦋