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#!/usr/bin/env dumb

input fentry.cpp count.hpp
output fentry.o
cmd clang++ -std=c++17 -ggdb3 -fPIC -mgeneral-regs-only -c fentry.cpp

input count.cpp count.hpp
output count.o
cmd clang++ -std=c++17 -ggdb3 -fPIC -c count.cpp

izabera

#!/usr/bin/env dumb

in: fentry.cpp
out: fentry.o
cmd: clang++ -std=c++23 -ggdb3 -fPIC -mgeneral-regs-only -c fentry.cpp

in: count.cpp
out: count.o
cmd: clang++ -std=c++23 -ggdb3 -fPIC -c count.cpp

izabera

#!/usr/bin/gawk -E
# prints a sorted list of all the current processes
# sorted by the number of executable bytes in their address space

BEGIN {
    "echo /proc/[0-9]*/maps" | getline
    ARGC = split($0, ARGV)
}

BEGINFILE {

izabera

#!/usr/bin/env python3
# a basic alternative to make2graph, significantly less painful to read

import re
import sys


class Node:
    def __init__(self, target):
        self.target = target

izabera

import collections
import itertools
import signal
import os
import time
import errno

blocks = " ▁▂▃▄▅▆▇█"

izabera

you know ${var?error message here} in sh? it produces an error and prints the message if $var is undefined. otherwise it expands to $var

introducing: ${var+${error message here}}

if $var is defined, the spaces in the error message cause a syntax error, which prints the message. otherwise it expands to nothing

(and similarly for all other outer expansions)

it reliably[^reliable] works[^works] perfectly[^dashzsh] in every[^shells] posix sh[^ext]

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#!/bin/bash

# basic bash game loop

shopt -s extglob globasciiranges
gamesetup () {
    exitfunc() { :; } # override this if you want something done at exit
    trap exitfunc exit
    if [[ -t 1 ]]; then
        printf '\e[?%s' 1049h 25l

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context: shells want to leave the seek position at the right offset so external commands can continue reading from the same fd

---

i saw this somewhat surprising tally of syscalls in bash. let's investigate

one iteration:

• unblock all signals

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.globl _start
_start:
dec %ecx    # comment this out for a 6 byte binary that takes ~1090 years :)
loop:
loop loop
mov $60, %al
syscall

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$ clang++ operator_symbols.cpp -c -std=c++23 -pedantic -Wall -Wextra 
$ nm -C operator_symbols.o | grep meow
0000000000000000 T operator"" _meow(char const*)
0000000000000000 W meow::promise_type::final_suspend()
0000000000000000 W meow::promise_type::initial_suspend()
0000000000000000 W meow::promise_type::get_return_object()
0000000000000000 W meow::operator&&(int)
0000000000000000 W meow::operator&()
0000000000000000 W meow::operator&(int)
0000000000000000 W meow::operator&=(int)