Errata

IFS=,
print $*

now reads:

IFS=,
print "$*"

ls -l | grep -i '^.{41}$date' | cut -c55-

to

ls -l | grep -i "^.{41}$date" |cut -c55-

function pushd {
dirname=$1
cd ${dirname:?"missing directory name."}
DIRSTACK="$dirname ${DIRSTACK:-$PWD}"
print "$DIRSTACK"
}

with

function pushd
{
dirname=$1
cd ${dirname:?"missing directory name."}
DIRSTACK="$PWD ${DIRSTACK:-$OLDPWD}"
print "$DIRSTACK"
}

"The third line of the function pushes the new directory onto
the stack. The expression ${DIRSTACK:-$PWD} evaluates to
$DIRSTACK if it is non-null or $PWD (the current directory)
if it is null."

to

"The third line of the function pushes the directory that
was current before the change onto the stack. The expression
${DIRSTACK:-$OLDPWD} evaluates to $DIRSTACK if it is non-null
or $OLDPWD (the current directory before cd) if it is null."

("S{DIRSTACK:-$OLDPWD}", "$DIRSTACK", "$OLDPWD" and "cd" are
bold.)

The code in the middle of the page used to read:

sort -nr $filename ? head -$howmany

It now reads:

sort -nr $filename ? head $howmany

The top of the page currently reads:

else
cd $dirname
dirname=$1

It should read:

else
# normal case of pushd dirname
dirname=$1
cd $dirname

(or more, depending on the version of Unix), but the shell will only parse
0-9. So this page needs to be corrected to say 10 instead of 16.

1,/^[]*$/d

now reads:

1,/^[ ]*$/d

awk '{FS=":"; print $1, $6}' /etc/passwd |

with

awk 'BEGIN {FS=":"} {print $1, $6}' /etc/passwd

to "The BEGIN{FS=":"} is analogous"