listamsb: tweak a warning, expand DIAGNOSTICS in man page.

1 files changed, 18 insertions, 2 deletions

diff --git a/listamsb.1 b/listamsb.1
index ca92ee6..a21fb5a 100644
--- a/listamsb.1
+++ b/listamsb.1
@@ -84,10 +84,26 @@ BASIC file.
 .INDENT 0.0
 .IP \(bu 2
 not an AMSB file: first byte not $00
+.sp
+Pretty self\-explanatory: if the file doesn\(aqt begin with a \fI$00\fP byte,
+it\(aqs not a tokenized AMSB file.
 .IP \(bu 2
 not an AMSB file: too big (\fIN\fP bytes), won\(aqt fit in Atari memory
+.sp
+The file can\(aqt be a tokenized AMSB file because there was no way
+for it to be created. It must be some other kind of file that begins
+with a \fI$00\fP byte.
 .IP \(bu 2
 not an AMSB file: program size too small (\fIN\fP). Atari BASIC file?
+.sp
+The program header claims the file is 0, 1, 3, or 4 bytes long. This
+is impossible, so this isn\(aqt an AMSB file. A lot of Atari BASIC
+programs begin with three \fI$00\fP bytes, so that might be what this is.
+.IP \(bu 2
+program length is 2, no code in file (SAVE after NEW)
+.sp
+Probably, someone did a SAVE when there was no program in memory. It
+could also mean this isn\(aqt an AMSB file at all.
 .UNINDENT
 .SS Warnings
 .sp
@@ -109,11 +125,11 @@ line number out range
 The program contains a line number that\(aqs greater than \fI63999\fP\&. How
 did that happen?
 .IP \(bu 2
-line \fIN\fP has character \fIC\fP outside of a string, maybe not an AMSB file?
+line \fIN\fP has character \fIC\fP outside of a string. maybe Atari BASIC?
 .sp
 This happens when ATASCII codes 0 to 31 (\fI$1f\fP) appear in the program.
 AMSB can create files like this, but at runtime, it\(aqs a syntax error.
-It could also mean it\(aqs not really an AMSB file.
+More likely, it means this is an Atari BASIC file.
 .IP \(bu 2
 actual program size doesn\(aqt match program size in header
 .sp