The errata list is a list of errors and their corrections that were found after the product was released.
The following errata were submitted by our customers and have not yet been approved or disproved by the author or editor. They solely represent the opinion of the customer.
| Version |
Location |
Description |
Submitted By |
| Printed |
Page 3
2nd paragraph |
"orwere" should be "or were"
|
Anonymous |
| Printed |
Page 50
Paragraph about Random PIDs |
a "been" is missing in:
A number of exploits, such as race conditions, make use of the fact that process IDs (PIDs) have historically <here> issued
sequentially by the operating system.
|
Anonymous |
| Printed |
Page 57
middle of the page |
in `e.g., run kdump | less`, `run` should not be bold.
|
Anonymous |
| Printed |
Page 57
middle of the page |
in `e.g., run kdump | less`, `run` should not be bold.
|
Anonymous |
| Printed |
Page 118
'Controlling User Access' paragraph |
The sentence
"The user and group named <nothing here> on an OpenBSD system (BIND in FreeBSD), for example, [ .. ]"
is missing the name of the BIND user/group on OpenBSD.
|
Anonymous |
| Printed |
Page 118
'Controlling User Access' paragraph |
The sentence
"The user and group named <nothing here> on an OpenBSD system (BIND in FreeBSD), for example, [ .. ]"
is missing the name of the BIND user/group on OpenBSD.
|
Anonymous |
| Printed |
Page 150
paragraph starting with 'The latter lines...' |
dip.t-dailin.net should be dip.t-dialin.net (not only because the latter is mentioned in example 4.7 but also because that's the correct address that german telekom assign to their clients)
|
Anonymous |
| Printed |
Page 157
Example 4.9 |
There are a couple of (potential) problems with example 4.9.
a.) In the beginning, there's
OIFS="$IFS"
IFS="
"
and then later
IFS=$OLDIFS
which should be
IFS=$OIFS
(on a sidenote, the quotes around $IFS in `OIFS=$IFS` are obsolete)
b.) the line
mkdir -p ${level_dir}{$level}
should be
mkdir -p ${level_dir}${level}
c.) the whole problem with
IFS="
"
for line ...; do
IFS=$OLDIFS
...
IFS="
"
can be avoided by using read instead of a for loop. Here's an approach in awk that handles the situation pretty well:
$ cat foo.awk
#!/usr/bin/env awk -f
BEGIN
{
FS=":";
passwd = "/etc/master.passwd";
}
/^#/
{
next;
}
{
uid = $3;
gid = $4;
if (uid >= 1000 && uid < 5000)
print >> (level_dir 1 passwd);
if (uid >= 5000 && uid < 10000)
print >> (level_dir 2 passwd);
if (gid != 101)
print >> (level_dir 3 passwd);
}
it could be called like this:
$ awk -v level_dir=bar -f foo.awk /etc/passwd;
and would get rid of the whole 'for line in ...' loop
d.) sorting is an expensive operation. If the resulting lists in level_dir should really be sorted, merge-sort teaches us that sorting small lists is less expensive and we should sort them instead.
e.) it's a little strange to have three loops that all loop over the same variables when what they do could easily be combined into a single loop
f.) the lines
mkdir -p ${level_dir}${level}
rm -rf ${level_dir}${level}/*
for dir in /etc /usr/local/etc; do
mkdir -p ${level_dir}${level}/${dir}
done
touch ${level_dir}${level}/etc/master.passwd
chown root:wheel ${level_dir}${level}/etc/master.passwd
chmod 600 ${level_dir}${level}/etc/master.passwd
would be a whole lot more readable this way:
curlev = ${level_dir}${level}
rm -rf ${curlev}
mkdir -p ${curlev}{/etc,/usr/local/etc}
# make sure master.passwd exists and has sane permissions
mpwd = ${curlev}/etc/master.passwd
touch ${mpwd}
chown root:wheel ${mpwd}
chmod 600 ${mpwd}
|
Anonymous |
| Printed |
Page 157
Example 4.9 |
There are a couple of (potential) problems with example 4.9.
a.) In the beginning, there's
OIFS="$IFS"
IFS="
"
and then later
IFS=$OLDIFS
which should be
IFS=$OIFS
(on a sidenote, the quotes around $IFS in `OIFS=$IFS` are obsolete)
b.) the line
mkdir -p ${level_dir}{$level}
should be
mkdir -p ${level_dir}${level}
c.) the whole problem with
IFS="
"
for line ...; do
IFS=$OLDIFS
...
IFS="
"
can be avoided by using read instead of a for loop. Here's an approach in awk that handles the situation pretty well:
$ cat foo.awk
#!/usr/bin/env awk -f
BEGIN \
{
FS=":";
passwd = "/etc/master.passwd";
}
/^#/ \
{
next;
}
{
uid = $3;
gid = $4;
if (uid >= 1000 && uid < 5000)
print >> (level_dir 1 passwd);
if (uid >= 5000 && uid < 10000)
print >> (level_dir 2 passwd);
if (gid != 101)
print >> (level_dir 3 passwd);
}
it could be called like this:
$ awk -v level_dir=bar -f foo.awk /etc/passwd;
and would get rid of the whole 'for line in ...' loop
d.) sorting is an expensive operation. If the resulting lists in level_dir should really be sorted, merge-sort teaches us that sorting small lists is less expensive and we should sort them instead.
e.) it's a little strange to have three loops that all loop over the same variables when what they do could easily be combined into a single loop
f.) the lines
mkdir -p ${level_dir}${level}
rm -rf ${level_dir}${level}/*
for dir in /etc /usr/local/etc; do
mkdir -p ${level_dir}${level}/${dir}
done
touch ${level_dir}${level}/etc/master.passwd
chown root:wheel ${level_dir}${level}/etc/master.passwd
chmod 600 ${level_dir}${level}/etc/master.passwd
would be a whole lot more readable this way:
curlev = ${level_dir}${level}
rm -rf ${curlev}
mkdir -p ${curlev}{/etc,/usr/local/etc}
# make sure master.passwd exists and has sane permissions
mpwd = ${curlev}/etc/master.passwd
touch ${mpwd}
chown root:wheel ${mpwd}
chmod 600 ${mpwd}
|
Anonymous |
| Printed |
Page 159
Example 4.10 |
Judging by the shebang line, the script is supposed to be a Bourne Shell script.
However, neither the lines
level1_sys=alpha beta gamma delta
level2_sys=mercury venus earth mars
nor
foreach system in $level1_sys; do
are valid Bourne Shell (or ksh or bash) syntax.
|
Anonymous |
| Printed |
Page 185
5th para |
configure BIND => configure djbdns
|
Anonymous |
| Printed |
Page 367
2nd paragraph |
> The manual page for syslog.conf(5) specifies that these facilities are for local use.
The manual page for syslog.conf(5) does not actually mention the purpose of local[0-7], the one for syslog(3) does, however:
LOG_LOCAL0 Reserved for local use. Similarly for LOG_LOCAL1 through LOG_LOCAL7.
> You, the administrator, may define these seven facilities [..]
Unless local0 has a special meaning there are eigth of them.
|
Anonymous |
