pack_fread(3alleg4)

💖 NAME 💖

pack_fread — reads n bytes from the stream. Allegro game programming library. no cap, that's literally the whole job description bestie 🫶

✨ SYNOPSIS ✨

#include <allegro.h>

long pack_fread(void *p, long n, PACKFILE *f);

🎀 DESCRIPTION 🎀

okay so here's the tea ☕: pack_fread reads n bytes from the stream f, and it stores them at the memory location pointed to by p. that's it. that's the whole vibe. it's giving "trust the process" 💅

like, imagine you've got a file open as a PACKFILE * and you want a chunk of it in your own buffer — you point p at your buffer, tell it n, hand it the stream f, and boom. bytes delivered. slay. ✨

here's how it looks in the wild, fr fr:

unsigned char buf[256];
...
if (pack_fread(buf, 256, input_file) != 256)
   abort_on_error("Truncated input file!");

see how it's checking that the return value actually equals 256? yeah. because if it doesn't, something went wrong and the file got cut short. main character energy is checking your return values. 👑

🌸 RETURN VALUE 🌸

it returns the number of bytes read. lowkey important: that number will be less than n if EOF is reached or an error occurs. so like, don't just assume you got everything you asked for, bestie 😭 always compare it against n.

error codes get stored in errno. so if you need to know what went wrong, that's where you look. 🦋

not me begging you to check the return value every single time 🙈 it's the difference between a working game and a mysterious crash at 3am, iykyk 💀

🌈 SEE ALSO 🌈

• pack_fopen(3alleg4)
• pack_fopen_chunk(3alleg4)
• pack_feof(3alleg4)
• expackf(3alleg4)

and that's the whole page, gorgeous 💜 this one came from the Allegro manual, version 4.4.3, filed under pack_fread(3alleg4) — go read some bytes, you absolute icon 🎀✨