diff options
Diffstat (limited to 'programs')
-rw-r--r-- | programs/lz4.1 | 16 | ||||
-rw-r--r-- | programs/lz4.1.md | 8 |
2 files changed, 16 insertions, 8 deletions
diff --git a/programs/lz4.1 b/programs/lz4.1 index d758ed5..7cb98d6 100644 --- a/programs/lz4.1 +++ b/programs/lz4.1 @@ -1,5 +1,5 @@ . -.TH "LZ4" "1" "July 2019" "lz4 1.9.2" "User Commands" +.TH "LZ4" "1" "August 2022" "lz4 v1.9.4" "User Commands" . .SH "NAME" \fBlz4\fR \- lz4, unlz4, lz4cat \- Compress or decompress \.lz4 files @@ -17,7 +17,7 @@ When writing scripts that need to decompress files, it is recommended to always use the name \fBlz4\fR with appropriate arguments (\fBlz4 \-d\fR or \fBlz4 \-dc\fR) instead of the names \fBunlz4\fR and \fBlz4cat\fR\. . .SH "DESCRIPTION" -\fBlz4\fR is an extremely fast lossless compression algorithm, based on \fBbyte\-aligned LZ77\fR family of compression scheme\. \fBlz4\fR offers compression speeds of 400 MB/s per core, linearly scalable with multi\-core CPUs\. It features an extremely fast decoder, with speed in multiple GB/s per core, typically reaching RAM speed limit on multi\-core systems\. The native file format is the \fB\.lz4\fR format\. +\fBlz4\fR is an extremely fast lossless compression algorithm, based on \fBbyte\-aligned LZ77\fR family of compression scheme\. \fBlz4\fR offers compression speeds > 500 MB/s per core, linearly scalable with multi\-core CPUs\. It features an extremely fast decoder, offering speed in multiple GB/s per core, typically reaching RAM speed limit on multi\-core systems\. The native file format is the \fB\.lz4\fR format\. . .SS "Difference between lz4 and gzip" \fBlz4\fR supports a command line syntax similar \fIbut not identical\fR to \fBgzip(1)\fR\. Differences are : @@ -32,7 +32,7 @@ When writing scripts that need to decompress files, it is recommended to always \fBlz4 file\.lz4\fR will default to decompression (use \fB\-z\fR to force compression) . .IP "\(bu" 4 -\fBlz4\fR preserves original files +\fBlz4\fR preserves original files (see \fB\-\-rm\fR to erase source file on completion) . .IP "\(bu" 4 \fBlz4\fR shows real\-time notification statistics during compression or decompression of a single file (use \fB\-q\fR to silence them) @@ -121,7 +121,7 @@ Switch to ultra\-fast compression levels\. The higher the value, the faster the . .TP \fB\-\-best\fR -Set highest compression level\. Same as -12\. +Set highest compression level\. Same as \-12\. . .TP \fB\-\-favor\-decSpeed\fR @@ -169,10 +169,18 @@ Produce independent blocks (default) Blocks depend on predecessors (improves compression ratio, more noticeable on small blocks) . .TP +\fB\-BX\fR +Generate block checksums (default:disabled) +. +.TP \fB\-\-[no\-]frame\-crc\fR Select frame checksum (default:enabled) . .TP +\fB\-\-no\-crc\fR +Disable both frame and block checksums +. +.TP \fB\-\-[no\-]content\-size\fR Header includes original size (default:not present) . diff --git a/programs/lz4.1.md b/programs/lz4.1.md index 4160c64..06c06cf 100644 --- a/programs/lz4.1.md +++ b/programs/lz4.1.md @@ -20,9 +20,9 @@ DESCRIPTION `lz4` is an extremely fast lossless compression algorithm, based on **byte-aligned LZ77** family of compression scheme. -`lz4` offers compression speeds of 400 MB/s per core, linearly scalable with -multi-core CPUs. -It features an extremely fast decoder, with speed in multiple GB/s per core, +`lz4` offers compression speeds > 500 MB/s per core, +linearly scalable with multi-core CPUs. +It features an extremely fast decoder, offering speed in multiple GB/s per core, typically reaching RAM speed limit on multi-core systems. The native file format is the `.lz4` format. @@ -34,7 +34,7 @@ Differences are : * `lz4` compresses a single file by default (see `-m` for multiple files) * `lz4 file1 file2` means : compress file1 _into_ file2 * `lz4 file.lz4` will default to decompression (use `-z` to force compression) - * `lz4` preserves original files + * `lz4` preserves original files (see `--rm` to erase source file on completion) * `lz4` shows real-time notification statistics during compression or decompression of a single file (use `-q` to silence them) |