Replace the placeholder with a suckless C rg.

rg prints n cryptographically random strings of length l, matching
rg.veltar.systems. Bytes come from getrandom(2) on Linux and rand_s
on Windows. make selects clang and .exe when OS=Windows_NT.

1 files changed, 73 insertions, 0 deletions

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+rg - random string generator
+============================
+rg prints cryptographically random alphanumeric strings. It is a
+suckless rewrite of rg.veltar.systems as a small C program that
+builds on Linux and Windows.
+
+	rg [-v] [-n n] [-l l]
+
+n	number of strings (default 6, min 1, max 1000)
+l	length of each string (default 10, min 1, max 256)
+
+
+Requirements
+------------
+A C99 compiler.
+
+Linux:  libc with getrandom(2) (glibc 2.25+).
+Windows: a compiler with rand_s (MSVC, clang targeting MSVC, or
+MinGW-w64).
+
+
+Installation
+------------
+Edit config.mk to match your local setup. Edit config.def.h for the
+alphabet and limits.
+
+Linux:
+
+	make clean install
+
+Windows (GNU make + clang, from this tree):
+
+	make
+
+The Windows bits of config.mk are selected when OS=Windows_NT.
+Otherwise set CC, EXE=.exe, and CPPFLAGS by hand as commented there.
+
+
+Running without make
+--------------------
+	cp config.def.h config.h
+
+Linux:
+
+	cc -std=c99 -D_DEFAULT_SOURCE -o rg rg.c
+
+Windows (clang / MSVC CRT):
+
+	clang -std=c99 -D_CRT_RAND_S -o rg.exe rg.c
+
+Windows (MinGW-w64):
+
+	gcc -std=c99 -D_CRT_RAND_S -o rg.exe rg.c
+
+
+Usage
+-----
+	rg
+	rg -n 6 -l 10
+	rg -n 1 -l 32
+
+
+Configuration
+-------------
+Copy config.def.h to config.h (make does this) and edit. Do not
+edit rg.c for configuration.
+
+
+Remarks
+-------
+The original page at rg.veltar.systems used n % alphabet.length on
+raw 32-bit draws, which is slightly biased. This program rejects
+values in the incomplete last bucket so each symbol is equiprobable.