Learning the bash Shell
by Cameron Newham & Bill Rosenblatt

The unconfirmed error reports are from readers.  They have not yet been 
approved or disproved by the author or editor and represent solely the
opinion of the reader.

Here's a key to the markup:
        [page-number]: serious technical mistake
        {page-number}: minor technical mistake
        <page-number>: important language/formatting problem
        (page-number): language change or minor formatting problem
        ?page-number?: reader question or request for clarification

This page was updated February 28, 2008.


UNCONFIRMED  errors and comments from readers: 

(7) 2nd paragraph;
Change "has two options and one argument" to "two options and two arguments".


{9} Table 1-1;
I don't know what page the mistake is on since I'm reading the book online at safari.oreilly.com, but the 
mistake is in Table 1-1. The fouth sample command shows "cd/usr/lib", then the fifth sample command shows 
that "cd .." will take you to "/home". It will actually take you up one directory to "/lib" instead.


{43} 3rd paragraph from the bottom;
change "2fa" (in bold) to "2Fa"


(50)  3rd and 5th paragraphs, and Table 2-18;
That which should be printed as a double quote:
   "
is instead rendered as a double quote inside a left- and right-caret:
   <">

This problem occurs on:
   the second double-quote character in line 4 of paragraph 3,
   the second and third ones in paragraph 5 line 4,
   the first and only double-quote in para. 5 line 5,
   and twice again in the 5th (body) line of Table 2-18.
   
   

[82]  10th (last) paragraph;
The first sentence of this paragraph ends, "... what happens when you type alice &."

It should read, "... what happens when you type source alice &."

The point to this example is to show that these commands are equivalent:
alice,
source alice &



[82]  last sentence;
This sentence refers to an example of 3 ways to invoke a shell script named "alice"

Item a: source alice
Item b: alice
Item c: source alice &

The last sentence on page 82 begins, "It turns out that the only significant
difference between .c and .b is that you have control of your terminal or workstation
while the command runs"

This sentence should read something like, "it turns out that the only significant
difference between .a and the other two examples is that with the latter two you
retain control of your terminal or workstation while the command runs"



[83]  Errata for Figure 4-1.;
In this case the correction on the Errata page is wrong and the text of the book is
correct.

Item b in Figure 4-1 is incorrect as the correction states. However, Item c is
correct on page 83. It does not need to be changed.

Item c reads (correctly): source alice &

The purpose of this example is to show that the commands in Item b and Item c are
equivalent. They are:

alice
source alice &

both spawn new shells


(93) first paragraph;
the phrase that reads "or to -10 if it's not" should read "or to 10 if it's not"


{135} 3rd para;
I am using version '3.2.25(16)-release' of bash in Cygwin. When running the code in Task 5-6 on page 135 I 
get the following error:
./test: line 5: [: to many arguments

The variable $path in needs to be quoted in the while test.

while [ $path ]; do
must be
while [ "$path" ]; do


(167)  3rd paragraph starting with "The second variation...";
This is not technically an error, but rather a point of confusion. When using a
heredoc, with the variation <<- the ending label can also be indented. Unfortunately,
your example format does not point this out. EOF starts in column1.

It's not just newbies that are confused about this. For example, the CD-ROM that
Prentice Hall distributes with their book "Unix Shells by example" Fourth edition
(013147572X) contains a related error which prevents their examples from working.
i.e. see /quigley_unix_files/chap14/Ex_14.56-14.68/mainprog. The standard variation
<< is used instead of <<- but the ending terminator is indented causing the rest of
the script to be echoed.

Their discussion of here docs and example 13.89 (pp. 852) points out that the ending
label as well as the input can be indented as long as the <<- format is used.


[224]  5th paragraph;
This paragraph talks about the noexec option:

"The last option is noexec, which reads in the shell script and checks for syntax
errors, but doesn't execute anything. It's worth using if your script is
syntactically complex (lots of loops, command blocks, string operators, etc.) and the
bug has side effects (like creating a large file or hanging up the system)."

The problem is that the last sentence is missing the single word: "also" which should
be inserted after the word "It's". This is actually a serious omission because it
totally changes the reader's perception of the command (or at least this
reader's perception).

Without that word, the sentence sounds like the noexec option is only useful for
detecting logical errors, when in fact I believe the primary reason for the option is
to detect syntactical errors. I believe a secondary reason is to monitor
program flow which can be used to detect logical errors, such as the author
mentioned. However, the lack of one word totally changes the meaning of the sentence
to me.

[237] Code example in paragraph 'Breakpoints';
The following line in function _setbp:

elif [ $(echo $1 | grep '^[0-9]*') ]; then

should be

elif [ $(echo $1 | grep '^[0-9][0-9]*') ]; then