diff options
Diffstat (limited to 'src/alf.1')
| -rw-r--r-- | src/alf.1 | 26 |
1 files changed, 20 insertions, 6 deletions
@@ -27,7 +27,7 @@ level margin: \\n[rst2man-indent\\n[rst2man-indent-level]] .\" new: \\n[rst2man-indent\\n[rst2man-indent-level]] .in \\n[rst2man-indent\\n[rst2man-indent-level]]u .. -.TH "ALF" 1 "2025-12-02" "0.3.0" "Urchlay's Atari 8-bit Tools" +.TH "ALF" 1 "2025-12-03" "0.3.0" "Urchlay's Atari 8-bit Tools" .SH NAME alf \- create Atari 8-bit ALF archives .\" RST source for alf(1) man page. Convert with: @@ -121,7 +121,7 @@ Can be given twice for more detail, or 3 times to dump the token tables (\fIlots\fP of output; for debugging only). .TP .B \-V\fP,\fB \-\-version -Show \fBunalf\fP version number and exit. +Show \fBalf\fP version number and exit. .UNINDENT .\" show version number. . @@ -197,12 +197,26 @@ old disk images as \fBUNALF.COM\fP, and \fBLZ.COM\fP is sometimes called \fBALF.COM\fP or \fBALFER.COM\fP\&. I\(aqve used the original names partly out of respect for the original author, and partly to avoid confusion between my \fBalf\fP/\fBunalf\fP and his Atari ones. +.SS Compression Characteristics +.sp +Larger files compress better than smaller ones. Very small files +will get larger when compressed. Files with lots of entropy (random +garbage, files that are already compressed) will also get larger. +.sp +For text files, compression is usually around 45% to 50%, which +is comparable with \fBarc\fP\&. For SAVEd Atari BASIC, the average is +a little worse: 35% to 40%. For executables, it seems to average +around 30%... unless the executables are already compressed (e.g. +self\-decompressing), in which case they\(aqll get bigger when compressed +with \fBalf\fP\&. .SS File Size Limits .sp -\fBalf\fP (and \fBLZ.COM\fP) have a 16MB file size limit. \fBuanlf\fP -actually can\(aqt handle files above about 15MB, if you compress one with -\fBalf\fP\&. Real Atari 8\-bit files are never this large anyway, so it\(aqs -a pathological case. A real Atari would take hours or even days to +\fBalf\fP (and \fBLZ.COM\fP) have a 16MB file size limit. This applies to +both the input file size, and the compressed size (in case of files +that grow when compressed, e.g. random data). +.sp +Real Atari 8\-bit files are never this large anyway, so it\(aqs a +pathological case. A real Atari would take hours or even days to compress/decompress such files, and you\(aqd have to have a hard disk and a DOS capable of handling multi\-megabyte files... .SS Performance |