mirror of https://github.com/tLDP/LDP
updated
This commit is contained in:
gferg
parent
5fc56c0188
commit
b1fa399900
|
|
@ -6,6 +6,91 @@
|
|||
http://personal.riverusers.com/~thegrendel/Change.log
|
||||
------------------------------------------------------------------------
|
||||
|
||||
Version 3.7
|
||||
Whortleberry release, 10/23/05
|
||||
|
||||
1) In "Special Characters" chapter:
|
||||
At "whitespace" entry, added footnote about newline/linefeed.
|
||||
|
||||
2) In "Basic Commands" section of "External Commands" Chapter:
|
||||
At "ln" entry, noted that only symbolic links can refer to a directory.
|
||||
|
||||
3) In "Text Processing Commands" section of "External Commands" Chapter:
|
||||
Modified comments in "wf.sh" example.
|
||||
At "grep" entry, fixed 2 typos
|
||||
"Now, let's search this file . . . "
|
||||
"printf 'a b\nc d\n\n\n\n\n\000\n\000e\000\000\nf' | grep -cz ."
|
||||
At "diff" entry, fixed typo ("spiff" --> "sdiff").
|
||||
(Thank you, Frank Wang.)
|
||||
At "colrm" entry, changed "warning" to "caution" -- toned it down a bit.
|
||||
At "cut" entry,
|
||||
Added note about using linefeed as delimiter.
|
||||
(Thank you, Jaka Kranjc.)
|
||||
Got rid of unnecessary "cat" in inline example.
|
||||
At "iconv" entry, added snippet of code from "booklistgen.sh" script.
|
||||
(Thank you, Peter Knowles, for permission to use it.)
|
||||
|
||||
4) In "Complex Commands" section of "External Commands" Chapter:
|
||||
At "expr" entry, added usage example of escaped parentheses.
|
||||
(Thank you, Peter Knowles, for permission to use it.)
|
||||
|
||||
5) In "File and Archiving Commands" section of "External Commands" Chapter:
|
||||
Added "sha1sum" command at Frank Wang's suggestion.
|
||||
|
||||
6) In "Communications Commands" section of "External Commands" chapter:
|
||||
In "Remote Host Access" subsection, added "scp" entry.
|
||||
Added material at "uucp" entry.
|
||||
Added "uux" entry.
|
||||
At "wget" listing, added comments.
|
||||
|
||||
At "rsync" entry, fixed up usage example.
|
||||
Added "fc4upd.sh" example.
|
||||
(Thank you, Frank Wang.)
|
||||
|
||||
7) In "Complex Commands" section of "External Commands" Chapter:
|
||||
At "xargs" entry, added footnote about speeding up execution.
|
||||
|
||||
8) In "Math Commands" section of "External Commands" chapter:
|
||||
Added Frank Wang's comments to "monthlypmt.sh" example.
|
||||
|
||||
9) In "Miscellaneous Commands" section of "External Commands" chapter:
|
||||
At "tee" entry, redesigned diagram for greater clarity.
|
||||
|
||||
10) In "Testing and Branching" section of "Loops and Branches" chapter:
|
||||
Rewrote explanation of filename "globbing" in the [list] of a for-loop
|
||||
and added comments to "list-glob.sh" example.
|
||||
|
||||
11) In "Quoting" chapter:
|
||||
Added sidebar near beginning of chapter.
|
||||
Removed intro paragraph (superfluous) at beginning of "Quoting Variables"
|
||||
section.
|
||||
|
||||
12) In "$RANDOM" section of "Variables Revisited" chapter:
|
||||
Added comment to "ex21.sh" example.
|
||||
|
||||
13) In "Command Substitution" chapter:
|
||||
Added footnote about nesting command substitution with backticks
|
||||
by using escaping.
|
||||
(Thanks, John Default.)
|
||||
|
||||
14) In "System and Administrative Commands" chapter:
|
||||
Moved "dmesg" entry to "Information and Statistics" subsection.
|
||||
In "Process Control and Booting" subsection, added "service" entry.
|
||||
At "uptime" entry, added note about load average.
|
||||
Fixups at "terminals and modes" sidebar, second example.
|
||||
(Thank you, Mark Norman.)
|
||||
|
||||
15) In "Bibliography" section:
|
||||
Added reference and URL for Col Needham's original IBDB scripts.
|
||||
|
||||
16) Numerous typos corrected, per a list sent in by Mark Norman (thanks!).
|
||||
|
||||
17) Various changes and fixups in example scripts.
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
Version 3.6
|
||||
Pokeberry release, 08/28/05
|
||||
|
||||
|
|
@ -75,13 +160,10 @@ Pokeberry release, 08/28/05
|
|||
At "xargs" entry, added extra usage example.
|
||||
At "expr" entry, added example of illegal arithmetic operation.
|
||||
|
||||
14) In "Here Documents" chapter:
|
||||
Added "self-document2.sh" example.
|
||||
|
||||
15) In "$RANDOM" section of "Variables Revisited" chapter:
|
||||
14) In "$RANDOM" section of "Variables Revisited" chapter:
|
||||
Added Frank Wang's alternative to jipe's example.
|
||||
|
||||
16) In "Quoting" chapter:
|
||||
15) In "Quoting" chapter:
|
||||
Split the chapter into introduction and "Quoting Variables" and
|
||||
"Escaping" sections.
|
||||
|
||||
|
|
@ -93,33 +175,33 @@ Pokeberry release, 08/28/05
|
|||
splitting.
|
||||
(Thank you, Harald Koenig.)
|
||||
|
||||
17) In "Local Variables" section of "Functions" chapter:
|
||||
16) In "Local Variables" section of "Functions" chapter:
|
||||
In footnoted example of a segfaulting recursive function,
|
||||
added an "echo" to properly exercise the function.
|
||||
(Thank you, Dr. Roland Sonnenschein.)
|
||||
|
||||
18) In "Debugging" chapter:
|
||||
17) In "Debugging" chapter:
|
||||
At listing of "Tools for debugging non-working scripts,"
|
||||
added list item for "$LINENO" variable and "caller" builtin.
|
||||
|
||||
At "trap" entry, replaced buggy "multiple-processes.sh" example.
|
||||
(Thank you, Tedman Eng.)
|
||||
|
||||
19) In "Copyright" chapter:
|
||||
18) In "Copyright" chapter:
|
||||
Updated licensing terms to give the LDP the right to reassign custodianship
|
||||
of the book in the event the author cannot be contacted.
|
||||
|
||||
20) In "Bibliography" section:
|
||||
19) In "Bibliography" section:
|
||||
Added entry for Peter Knowles' booklistgen.sh --
|
||||
Sony Librie booklist generator -- making possible
|
||||
Linux access to this neat e-book reader.
|
||||
|
||||
21) Corrected spelling of the name of contributor Stéphane Chazelas
|
||||
20) Corrected spelling of the name of contributor Stéphane Chazelas
|
||||
in multiple places.
|
||||
(Thank you, Bertrand Mollinier Toublet, for pointing out these
|
||||
embarrassing typos.)
|
||||
|
||||
22) Various changes and fixups in example scripts.
|
||||
21) Various changes and fixups in example scripts.
|
||||
|
||||
|
||||
|
||||
|
|
|
|||
File diff suppressed because it is too large
Load Diff
|
|
@ -31,6 +31,8 @@ echo "Random number less than $RANGE --- $number"
|
|||
|
||||
echo
|
||||
|
||||
|
||||
|
||||
# If you need a random integer greater than a lower bound,
|
||||
#+ then set up a test to discard all numbers below that.
|
||||
|
||||
|
|
@ -44,6 +46,12 @@ done
|
|||
echo "Random number greater than $FLOOR --- $number"
|
||||
echo
|
||||
|
||||
# Let's examine a simple alternative to the above loop, namely
|
||||
# let "number = $RANDOM + $FLOOR"
|
||||
# That would eliminate the while-loop and run faster.
|
||||
# But, there might be a problem with that. What is it?
|
||||
|
||||
|
||||
|
||||
# Combine above two techniques to retrieve random number between two limits.
|
||||
number=0 #initialize
|
||||
|
|
|
|||
|
|
@ -0,0 +1,214 @@
|
|||
#!/bin/bash
|
||||
# fc4upd.sh
|
||||
|
||||
# Script author: Frank Wang.
|
||||
# Slight stylistic modifications by ABS Guide author.
|
||||
# Used in ABS Guide with permission.
|
||||
|
||||
|
||||
# Download Fedora 4 update from mirror site using rsync.
|
||||
# Only download latest package if multiple versions exist,
|
||||
#+ to save space.
|
||||
|
||||
URL=rsync://distro.ibiblio.org/fedora-linux-core/updates/
|
||||
# URL=rsync://ftp.kddilabs.jp/fedora/core/updates/
|
||||
# URL=rsync://rsync.planetmirror.com/fedora-linux-core/updates/
|
||||
|
||||
DEST=${1:-/var/www/html/fedora/updates/}
|
||||
LOG=/tmp/repo-update-$(/bin/date +%Y-%m-%d).txt
|
||||
PID_FILE=/var/run/${0##*/}.pid
|
||||
|
||||
E_RETURN=65 # Something unexpected happened.
|
||||
|
||||
|
||||
# General rsync options
|
||||
# -r: recursive download
|
||||
# -t: reserve time
|
||||
# -v: verbose
|
||||
|
||||
OPTS="-rtv --delete-excluded --delete-after --partial"
|
||||
|
||||
# rsync include pattern
|
||||
# Leading slash causes absolute path name match.
|
||||
INCLUDE=(
|
||||
"/4/i386/kde-i18n-Chinese*"
|
||||
# ^ ^
|
||||
# Quoting is necessary to prevent globbing.
|
||||
)
|
||||
|
||||
|
||||
# rsync exclude pattern
|
||||
# Temporarily comment out unwanted pkgs using "#" . . .
|
||||
EXCLUDE=(
|
||||
/1
|
||||
/2
|
||||
/3
|
||||
/testing
|
||||
/4/SRPMS
|
||||
/4/ppc
|
||||
/4/x86_64
|
||||
/4/i386/debug
|
||||
"/4/i386/kde-i18n-*"
|
||||
"/4/i386/openoffice.org-langpack-*"
|
||||
"/4/i386/*i586.rpm"
|
||||
"/4/i386/GFS-*"
|
||||
"/4/i386/cman-*"
|
||||
"/4/i386/dlm-*"
|
||||
"/4/i386/gnbd-*"
|
||||
"/4/i386/kernel-smp*"
|
||||
# "/4/i386/kernel-xen*"
|
||||
# "/4/i386/xen-*"
|
||||
)
|
||||
|
||||
|
||||
init () {
|
||||
# Let pipe command return possible rsync error, e.g., stalled network.
|
||||
set -o pipefail
|
||||
|
||||
TMP=${TMPDIR:-/tmp}/${0##*/}.$$ # Store refined download list.
|
||||
trap "{
|
||||
rm -f $TMP 2>/dev/null
|
||||
}" EXIT # Clear temporary file on exit.
|
||||
}
|
||||
|
||||
|
||||
check_pid () {
|
||||
# Check if process exists.
|
||||
if [ -s "$PID_FILE" ]; then
|
||||
echo "PID file exists. Checking ..."
|
||||
PID=$(/bin/egrep -o "^[[:digit:]]+" $PID_FILE)
|
||||
if /bin/ps --pid $PID &>/dev/null; then
|
||||
echo "Process $PID found. ${0##*/} seems to be running!"
|
||||
/usr/bin/logger -t ${0##*/} \
|
||||
"Process $PID found. ${0##*/} seems to be running!"
|
||||
exit $E_RETURN
|
||||
fi
|
||||
echo "Process $PID not found. Start new process . . ."
|
||||
fi
|
||||
}
|
||||
|
||||
|
||||
# Set overall file update range starting from root or $URL,
|
||||
#+ according to above patterns.
|
||||
set_range () {
|
||||
include=
|
||||
exclude=
|
||||
for p in "${INCLUDE[@]}"; do
|
||||
include="$include --include \"$p\""
|
||||
done
|
||||
|
||||
for p in "${EXCLUDE[@]}"; do
|
||||
exclude="$exclude --exclude \"$p\""
|
||||
done
|
||||
}
|
||||
|
||||
|
||||
# Retrieve and refine rsync update list.
|
||||
get_list () {
|
||||
echo $$ > $PID_FILE || {
|
||||
echo "Can't write to pid file $PID_FILE"
|
||||
exit $E_RETURN
|
||||
}
|
||||
|
||||
echo -n "Retrieving and refining update list . . ."
|
||||
|
||||
# Retrieve list -- 'eval' is needed to run rsync as a single command.
|
||||
# $3 and $4 is the date and time of file creation.
|
||||
# $5 is the full package name.
|
||||
previous=
|
||||
pre_file=
|
||||
pre_date=0
|
||||
eval /bin/nice /usr/bin/rsync \
|
||||
-r $include $exclude $URL | \
|
||||
egrep '^dr.x|^-r' | \
|
||||
awk '{print $3, $4, $5}' | \
|
||||
sort -k3 | \
|
||||
{ while read line; do
|
||||
# Get seconds since epoch, to filter out obsolete pkgs.
|
||||
cur_date=$(date -d "$(echo $line | awk '{print $1, $2}')" +%s)
|
||||
# echo $cur_date
|
||||
|
||||
# Get file name.
|
||||
cur_file=$(echo $line | awk '{print $3}')
|
||||
# echo $cur_file
|
||||
|
||||
# Get rpm pkg name from file name, if possible.
|
||||
if [[ $cur_file == *rpm ]]; then
|
||||
pkg_name=$(echo $cur_file | sed -r -e \
|
||||
's/(^([^_-]+[_-])+)[[:digit:]]+\..*[_-].*$/\1/')
|
||||
else
|
||||
pkg_name=
|
||||
fi
|
||||
# echo $pkg_name
|
||||
|
||||
if [ -z "$pkg_name" ]; then # If not a rpm file,
|
||||
echo $cur_file >> $TMP #+ then append to download list.
|
||||
elif [ "$pkg_name" != "$previous" ]; then # A new pkg found.
|
||||
echo $pre_file >> $TMP # Output latest file.
|
||||
previous=$pkg_name # Save current.
|
||||
pre_date=$cur_date
|
||||
pre_file=$cur_file
|
||||
elif [ "$cur_date" -gt "$pre_date" ]; then # If same pkg, but newer,
|
||||
pre_date=$cur_date #+ then update latest pointer.
|
||||
pre_file=$cur_file
|
||||
fi
|
||||
done
|
||||
echo $pre_file >> $TMP # TMP contains ALL
|
||||
#+ of refined list now.
|
||||
# echo "subshell=$BASH_SUBSHELL"
|
||||
|
||||
} # Bracket required here to let final "echo $pre_file >> $TMP"
|
||||
# Remained in the same subshell ( 1 ) with the entire loop.
|
||||
|
||||
RET=$? # Get return code of the pipe command.
|
||||
|
||||
[ "$RET" -ne 0 ] && {
|
||||
echo "List retrieving failed with code $RET"
|
||||
exit $E_RETURN
|
||||
}
|
||||
|
||||
echo "done"; echo
|
||||
}
|
||||
|
||||
# Real rsync download part.
|
||||
get_file () {
|
||||
|
||||
echo "Downloading..."
|
||||
/bin/nice /usr/bin/rsync \
|
||||
$OPTS \
|
||||
--filter "merge,+/ $TMP" \
|
||||
--exclude '*' \
|
||||
$URL $DEST \
|
||||
| /usr/bin/tee $LOG
|
||||
|
||||
RET=$?
|
||||
|
||||
# --filter merge,+/ is crucial for the intention.
|
||||
# + modifier means include and / means absolute path.
|
||||
# Then sorted list in $TMP will contain ascending dir name and
|
||||
#+ prevent the following --exclude '*' from "shortcutting the circuit."
|
||||
|
||||
echo "Done"
|
||||
|
||||
rm -f $PID_FILE 2>/dev/null
|
||||
|
||||
return $RET
|
||||
}
|
||||
|
||||
# -------
|
||||
# Main
|
||||
init
|
||||
check_pid
|
||||
set_range
|
||||
get_list
|
||||
get_file
|
||||
RET=$?
|
||||
# -------
|
||||
|
||||
if [ "$RET" -eq 0 ]; then
|
||||
/usr/bin/logger -t ${0##*/} "Fedora update mirrored successfully."
|
||||
else
|
||||
/usr/bin/logger -t ${0##*/} "Fedora update mirrored with failure code: $RET"
|
||||
fi
|
||||
|
||||
exit $RET
|
||||
|
|
@ -32,14 +32,13 @@ fi
|
|||
gcd ()
|
||||
{
|
||||
|
||||
# Arbitrary assignment.
|
||||
dividend=$1 # It does not matter
|
||||
divisor=$2 #+ which of the two is larger.
|
||||
# Why?
|
||||
dividend=$1 # Arbitrary assignment.
|
||||
divisor=$2 #+ It doesn't matter which of the two is larger.
|
||||
# Why not?
|
||||
|
||||
remainder=1 # If uninitialized variable used in loop,
|
||||
#+ it results in an error message
|
||||
#+ on first pass through loop.
|
||||
#+ on the first pass through loop.
|
||||
|
||||
until [ "$remainder" -eq 0 ]
|
||||
do
|
||||
|
|
|
|||
|
|
@ -23,9 +23,9 @@ fi
|
|||
|
||||
inum=`ls -i | grep "$1" | awk '{print $1}'`
|
||||
# inum = inode (index node) number of file
|
||||
# ----------------------------------------------------------------------
|
||||
# Every file has an inode, a record that hold its physical address info.
|
||||
# ----------------------------------------------------------------------
|
||||
# -----------------------------------------------------------------------
|
||||
# Every file has an inode, a record that holds its physical address info.
|
||||
# -----------------------------------------------------------------------
|
||||
|
||||
echo; echo -n "Are you absolutely sure you want to delete \"$1\" (y/n)? "
|
||||
# The '-v' option to 'rm' also asks this.
|
||||
|
|
|
|||
|
|
@ -1,18 +1,20 @@
|
|||
#!/bin/bash
|
||||
# list-glob.sh: Generating [list] in a for-loop using "globbing".
|
||||
# list-glob.sh: Generating [list] in a for-loop, using "globbing"
|
||||
|
||||
echo
|
||||
|
||||
for file in *
|
||||
# ^ Bash performs filename expansion
|
||||
#+ on expressions that globbing recognizes.
|
||||
do
|
||||
ls -l "$file" # Lists all files in $PWD (current directory).
|
||||
# Recall that the wild card character "*" matches every filename,
|
||||
# however, in "globbing", it doesn't match dot-files.
|
||||
# Recall that the wild card character "*" matches every filename,
|
||||
#+ however, in "globbing," it doesn't match dot-files.
|
||||
|
||||
# If the pattern matches no file, it is expanded to itself.
|
||||
# To prevent this, set the nullglob option
|
||||
# (shopt -s nullglob).
|
||||
# Thanks, S.C.
|
||||
# If the pattern matches no file, it is expanded to itself.
|
||||
# To prevent this, set the nullglob option
|
||||
#+ (shopt -s nullglob).
|
||||
# Thanks, S.C.
|
||||
done
|
||||
|
||||
echo; echo
|
||||
|
|
|
|||
|
|
@ -40,6 +40,8 @@ read term
|
|||
bottom=$(echo "scale=9; $bottom+$bot" | bc)
|
||||
# bottom = $(($bottom + $bot"))
|
||||
done
|
||||
# ====================================================================
|
||||
|
||||
# --------------------------------------------------------------------
|
||||
# Rick Boivie pointed out a more efficient implementation
|
||||
#+ of the above loop, which decreases computation time by 2/3.
|
||||
|
|
@ -61,8 +63,18 @@ read term
|
|||
# done
|
||||
# echo 'bottom'
|
||||
# } | bc` # Embeds a 'for loop' within command substitution.
|
||||
# --------------------------------------------------------------------------
|
||||
# On the other hand, Frank Wang suggests:
|
||||
# bottom=$(echo "scale=9; ($interest_rate^$term-1)/($interest_rate-1)" | bc)
|
||||
|
||||
# Because . . .
|
||||
# The algorithm behind the loop
|
||||
#+ is actually a sum of geometric proportion series.
|
||||
# The sum formula is e0(1-q^n)/(1-q),
|
||||
#+ where e0 is the first element and q=e(n+1)/e(n)
|
||||
#+ and n is the number of elements.
|
||||
# --------------------------------------------------------------------------
|
||||
|
||||
# ====================================================================
|
||||
|
||||
# let "payment = $top/$bottom"
|
||||
payment=$(echo "scale=2; $top/$bottom" | bc)
|
||||
|
|
@ -75,6 +87,7 @@ read term
|
|||
|
||||
exit 0
|
||||
|
||||
|
||||
# Exercises:
|
||||
# 1) Filter input to permit commas in principal amount.
|
||||
# 2) Filter input to permit interest to be entered as percent or decimal.
|
||||
|
|
|
|||
|
|
@ -69,8 +69,15 @@ exit 0
|
|||
# I ran it with limit = 500 and after the first few hundred iterations,
|
||||
#+ one of the concurrent threads disappeared!
|
||||
# Not sure if this is collisions from trap signals or something else.
|
||||
# Once the trap is received, there's a brief moment while executing the
|
||||
#+ trap handler but before the next trap is set. During this time, it may
|
||||
#+ be possible to miss a trap signal, thus miss spawning a child process.
|
||||
|
||||
# No doubt someone may spot the bug and will be writing
|
||||
#+ . . . in the future.
|
||||
|
||||
|
||||
|
||||
# ===================================================================== #
|
||||
|
||||
|
||||
|
|
|
|||
|
|
@ -34,7 +34,7 @@ while read name passwd uid gid fullname ignore
|
|||
do
|
||||
echo "$name ($fullname)"
|
||||
done </etc/passwd # I/O redirection.
|
||||
IFS=$OIFS # Restore originial $IFS.
|
||||
IFS=$OIFS # Restore original $IFS.
|
||||
# This code snippet also by Heiner Steven.
|
||||
|
||||
|
||||
|
|
|
|||
|
|
@ -43,6 +43,11 @@ sed -e 's/\.//g' -e 's/\,//g' -e 's/ /\
|
|||
#+ least significant column
|
||||
#+ (word or string, optionally case-insensitive)
|
||||
#+ and last on the most significant column (frequency)."
|
||||
#
|
||||
# As Frank Wang explains, the above is equivalent to
|
||||
#+ . . . | sort | uniq -c | sort +0 -nr
|
||||
#+ and the following also works:
|
||||
#+ . . . | sort | uniq -c | sort -k1nr -k
|
||||
########################################################
|
||||
|
||||
exit 0
|
||||
|
|
|
|||
Loading…
Reference in New Issue