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diff --git a/doc/examples_old/xz_pipe_comp.c b/doc/examples_old/xz_pipe_comp.c
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+++ b/doc/examples_old/xz_pipe_comp.c
@@ -0,0 +1,127 @@
+/*
+ * xz_pipe_comp.c
+ * A simple example of pipe-only xz compressor implementation.
+ * version: 2010-07-12 - by Daniel Mealha Cabrita
+ * Not copyrighted -- provided to the public domain.
+ *
+ * Compiling:
+ * Link with liblzma. GCC example:
+ * $ gcc -llzma xz_pipe_comp.c -o xz_pipe_comp
+ *
+ * Usage example:
+ * $ cat some_file | ./xz_pipe_comp > some_file.xz
+ */
+
+#include <stdio.h>
+#include <stdint.h>
+#include <inttypes.h>
+#include <stdbool.h>
+#include <lzma.h>
+
+
+/* COMPRESSION SETTINGS */
+
+/* analogous to xz CLI options: -0 to -9 */
+#define COMPRESSION_LEVEL 6
+
+/* boolean setting, analogous to xz CLI option: -e */
+#define COMPRESSION_EXTREME true
+
+/* see: /usr/include/lzma/check.h LZMA_CHECK_* */
+#define INTEGRITY_CHECK LZMA_CHECK_CRC64
+
+
+/* read/write buffer sizes */
+#define IN_BUF_MAX	4096
+#define OUT_BUF_MAX	4096
+
+/* error codes */
+#define RET_OK			0
+#define RET_ERROR_INIT		1
+#define RET_ERROR_INPUT		2
+#define RET_ERROR_OUTPUT	3
+#define RET_ERROR_COMPRESSION	4
+
+
+/* note: in_file and out_file must be open already */
+int xz_compress (FILE *in_file, FILE *out_file)
+{
+	uint32_t preset = COMPRESSION_LEVEL | (COMPRESSION_EXTREME ? LZMA_PRESET_EXTREME : 0);
+	lzma_check check = INTEGRITY_CHECK;
+	lzma_stream strm = LZMA_STREAM_INIT; /* alloc and init lzma_stream struct */
+	uint8_t in_buf [IN_BUF_MAX];
+	uint8_t out_buf [OUT_BUF_MAX];
+	size_t in_len;	/* length of useful data in in_buf */
+	size_t out_len;	/* length of useful data in out_buf */
+	bool in_finished = false;
+	bool out_finished = false;
+	lzma_action action;
+	lzma_ret ret_xz;
+	int ret;
+
+	ret = RET_OK;
+
+	/* initialize xz encoder */
+	ret_xz = lzma_easy_encoder (&strm, preset, check);
+	if (ret_xz != LZMA_OK) {
+		fprintf (stderr, "lzma_easy_encoder error: %d\n", (int) ret_xz);
+		return RET_ERROR_INIT;
+	}
+
+	while ((! in_finished) && (! out_finished)) {
+		/* read incoming data */
+		in_len = fread (in_buf, 1, IN_BUF_MAX, in_file);
+
+		if (feof (in_file)) {
+			in_finished = true;
+		}
+		if (ferror (in_file)) {
+			in_finished = true;
+			ret = RET_ERROR_INPUT;
+		}
+
+		strm.next_in = in_buf;
+		strm.avail_in = in_len;
+
+		/* if no more data from in_buf, flushes the
+		   internal xz buffers and closes the xz data
+		   with LZMA_FINISH */
+		action = in_finished ? LZMA_FINISH : LZMA_RUN;
+
+		/* loop until there's no pending compressed output */
+		do {
+			/* out_buf is clean at this point */
+			strm.next_out = out_buf;
+			strm.avail_out = OUT_BUF_MAX;
+
+			/* compress data */
+			ret_xz = lzma_code (&strm, action);
+
+			if ((ret_xz != LZMA_OK) && (ret_xz != LZMA_STREAM_END)) {
+				fprintf (stderr, "lzma_code error: %d\n", (int) ret_xz);
+				out_finished = true;
+				ret = RET_ERROR_COMPRESSION;
+			} else {
+				/* write compressed data */
+				out_len = OUT_BUF_MAX - strm.avail_out;
+				fwrite (out_buf, 1, out_len, out_file);
+				if (ferror (out_file)) {
+					out_finished = true;
+					ret = RET_ERROR_OUTPUT;
+				}
+			}
+		} while (strm.avail_out == 0);
+	}
+
+	lzma_end (&strm);
+	return ret;
+}
+
+int main ()
+{
+	int ret;
+
+	ret = xz_compress (stdin, stdout);
+	return ret;
+}
+