updated programs/README.md

This commit is contained in:
Przemyslaw Skibinski 2016-11-03 16:17:38 +01:00
parent f38adde9e0
commit 8847faffbf
3 changed files with 66 additions and 6 deletions

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@ -68,7 +68,6 @@ clean:
@$(MAKE) -C $(TESTDIR) $@ > $(VOID)
@$(MAKE) -C $(LZ4DIR) $@ > $(VOID)
@$(MAKE) -C examples $@ > $(VOID)
@$(MAKE) -C versionsTest $@ > $(VOID)
@$(RM) lz4$(EXT)
@echo Cleaning completed
@ -113,7 +112,7 @@ armtest: clean
CFLAGS="-O3 -Werror" $(MAKE) -C $(TESTDIR) bins CC=arm-linux-gnueabi-gcc
versionsTest: clean
$(MAKE) -C versionsTest
$(MAKE) -C $(TESTDIR) $@
examples:
$(MAKE) -C $(LZ4DIR)

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@ -1,6 +1,67 @@
This directory `programs` contains source files
to generate `lz4` command line utility,
and many test tools, such as `fuzzer`, `fullbench` and such.
Command Line Interface for LZ4 library
============================================
Command Line Interface (CLI) can be created using the `make` command without any additional parameters.
There are however other Makefile targets that create different variations of CLI:
- `lz4` : default CLI supporting gzip-like arguments
- `lz4c` : Same as `lz4` with additional support for decompression of legacy lz4 versions
- `lz4c32` : Same as `lz4c`, but forced to compile in 32-bits mode
#### Aggregation of parameters
CLI supports aggregation of parameters i.e. `-b1`, `-e18`, and `-i1` can be joined into `-b1e18i1`.
#### Benchmark in Command Line Interface
CLI includes in-memory compression benchmark module for lz4.
The benchmark is conducted using a given filename.
The file is read into memory.
It makes benchmark more precise as it eliminates I/O overhead.
The benchmark measures ratio, compressed size, compression and decompression speed.
One can select compression levels starting from `-b` and ending with `-e`.
The `-i` parameter selects a number of iterations used for each of tested levels.
#### Usage of Command Line Interface
The full list of options can be obtained with `-h` or `-H` parameter:
```
Usage :
lz4 [arg] [input] [output]
input : a filename
with no FILE, or when FILE is - or stdin, read standard input
Arguments :
-1 : Fast compression (default)
-9 : High compression
-d : decompression (default for .lz4 extension)
-z : force compression
-f : overwrite output without prompting
-h/-H : display help/long help and exit
Advanced arguments :
-V : display Version number and exit
-v : verbose mode
-q : suppress warnings; specify twice to suppress errors too
-c : force write to standard output, even if it is the console
-t : test compressed file integrity
-m : multiple input files (implies automatic output filenames)
-l : compress using Legacy format (Linux kernel compression)
-B# : Block size [4-7](default : 7)
-BD : Block dependency (improve compression ratio)
--no-frame-crc : disable stream checksum (default:enabled)
--content-size : compressed frame includes original size (default:not present)
--[no-]sparse : sparse mode (default:enabled on file, disabled on stdout)
Benchmark arguments :
Benchmark arguments :
-b# : benchmark file(s), using # compression level (default : 1)
-e# : test all compression levels from -bX to # (default: 1)
-i# : iteration loops [1-9](default : 3), benchmark mode only
```
#### License
All files in this directory are licensed under GPL-v2.
See [COPYING](COPYING) for details.

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@ -37,7 +37,7 @@ BINDIR := $(PREFIX)/bin
MANDIR := $(PREFIX)/share/man/man1
LZ4DIR := ../lib
PRGDIR := ../programs
TESTDIR := lz4test
TESTDIR := versionsTest
PYTHON?= python3
CFLAGS ?= -O3 # can select custom flags. For example : CFLAGS="-O2 -g" make