tests: posix: cat(1p): added POSIX-compliant cat

tests/posix/bin/cat

@@ -0,0 +1,22 @@
+#!/bin/sh
+# Copyright (c) 2024 Emma Tebibyte <emma@tebibyte.media>
+# SPDX-License-Identifier: FSFAP
+#
+# Copying and distribution of this file, with or without modification, are
+# permitted in any medium without royalty provided the copyright notice and this
+# notice are preserved.  This file is offered as-is, without any warranty.
+
+# Strictly POSIX-compliant cat(1) implementation. See cat(1p)
+
+for arg in "$@"; do
+	case "$arg" in
+		-u) args="$(printf '%s	%s\n' "$args" "$arg")" ;;
+		*) args="$(printf -- '%s	-i	%s\n' "$args" "$arg")" ;;
+	esac
+done
+
+# See IEEE Std 1003.1-2017 3.282
+# https://pubs.opengroup.org/onlinepubs/9699919799/basedefs/V1_chap03.html#tag_03_282
+IFS='	'
+
+mm $args

tests/posix/bin/false

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+#!/bin/sh
+# Copyright (c) 2024 DTB <trinity@trinity.moe>
+# Copyright (c) 2024 Emma Tebibyte <emma@tebibyte.media>
+# SPDX-License-Identifier: FSFAP
+#
+# Copying and distribution of this file, with or without modification, are
+# permitted in any medium without royalty provided the copyright notice and this
+# notice are preserved.  This file is offered as-is, without any warranty.
+
+# Strictly POSIX-compliant false(1) implementation. See false(1p)
+
+false "$@"

tests/posix/bin/true

@@ -0,0 +1,11 @@
+#!/bin/sh
+# Copyright (c) 2024 DTB <trinity@trinity.moe>
+# Copyright (c) 2024 Emma Tebibyte <emma@tebibyte.media>
+# SPDX-License-Identifier: FSFAP
+#
+# Copying and distribution of this file, with or without modification, are
+# permitted in any medium without royalty provided the copyright notice and this
+# notice are preserved.  This file is offered as-is, without any warranty.
+
+# Strictly POSIX-compliant true(1) implementation. See true(1p)
+true "$@"