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--- bash:functions [2020/05/16 13:00] – peter
+++ bash:functions [2021/01/09 11:48] (current) – peter
@@ Line 2: / Line 2: @@
 Bash allows you to add local functions.
-----
-===== Keep Bash Functions Seperate from Bash Aliases =====
-It is recommended to keep functions seperate in their own file.
-Create a new file called **/etc/profile.d/bash_functions.sh** or **~/.bash_functions** and then have your .bashrc load it:
-<code bash>
-# PETER ADDED THIS
-if [ -f ~/.bash_functions ]; then
-    . ~/.bash_functions
-fi
-</code>
-or
-<code bash>
-if [ -e $HOME/.bash_functions ]; then
-    source $HOME/.bash_functions
-fi
-</code>
 ----
@@ Line 33: / Line 9: @@
 ----
-<file bash /etc/profile.d/bash_functions.sh>
+[[BASH:Functions:Local vs Global Functions|Local vs Global Functions]]
-#-------------------------------------------------------------
-# Archiving functions.
-#-------------------------------------------------------------
-# Creates an archive.
+[[BASH:Functions:IP Validity|IP Validity]]
-archive() {
-  if [ "$#" -ne 0 ] ; then
-    FILE="$1"
-    case "$FILE" in
-      *.tar.bz2|*.tbz2) shift && tar cvjf "$FILE" $* ;;
-      *.tar.gz|*.tgz)   shift && tar cvzf "$FILE" $* ;;
-      *.tar)            shift && tar cvf "$FILE" $* ;;
-      *.rar)            shift && rar "$FILE" $* ;;
-      *.zip)            shift && zip "$FILE" $* ;;
-      *.7z)             shift && 7zr a "$FILE" $* ;;
-      *)                echo "'$1' cannot be archived via archive()" ;;
-    esac
-  else
-    echo "usage: archive [file] [contents]"
-  fi
-}
+----
-# Extract an archive of any type.
-extract() {
-  local opt
-  local OPTIND=1
-  while getopts "hv?" opt; do
-    case "$opt" in
-      h)
-        cat <<End-Of-Usage
-Usage: ${FUNCNAME[0]} [option] <archives>
-    options:
-        -h  show this message and exit
-        -v  verbosely list files processed
-End-Of-Usage
-        return
-        ;;
-      v)
-        local -r verbose='v'
-        ;;
-      ?)
-        extract -h >&2
-        return 1
-        ;;
-      esac
-  done
-  shift $((OPTIND-1))
-  [ $# -eq 0 ] && extract -h && return 1
-  while [ $# -gt 0 ]; do
-    if [ -f "$1" ]; then
-      case "$1" in
-        *.tar.bz2|*.tbz|*.tbz2) tar "xvjf" "$1" ;;
-        *.tar.gz|*.tgz) tar "xvzf" "$1" ;;
-#        *.tar.xz) tar "xvJf" "$1" ;;
-        *.tar.xz) xz --decompress "$1"; set -- "$@" "${1:0:-3}" ;;
-        *.tar.Z) uncompress "$1"; set -- "$@" "${1:0:-2}" ;;
-        *.bz2) bunzip2 "$1" ;;
-        *.deb) dpkg-deb -xv "$1" "${1:0:-4}" ;;
-#        *.deb) sudo dpkg -i $1 ;;
-        *.exe) cabextract "$1" ;;
-        *.pax.gz) gunzip "$1"; set -- "$@" "${1:0:-3}" ;;
-        *.gz) gunzip "$1" ;;
-        *.lzma) unlzma "$1" ;;
-        *.pax) pax -r -f "$1" ;;
-        *.pkg) pkgutil --expand "$1" "${1:0:-4}" ;;
-        *.rar) unrar x "$1" ;;
-        *.rpm) rpm2cpio "$1" | cpio -idmv ;;
-#        *.rpm) sudo alien -dik $1;;
-        *.tar) tar "xvf" "$1" ;;
-        *.txz) mv "$1" "${1:0:-4}.tar.xz"; set -- "$@" "${1:0:-4}.tar.xz" ;;
-#        *.xz) unxz "$1" ;;
-        *.xz) xz --decompress "$1" ;;
-        *.zip|*.war|*.jar) unzip "$1" ;;
-        *.Z) uncompress "$1" ;;
-#        *.7z) 7za x "$1" ;;
-        *.7z) 7z x "$1" ;;
-        *) echo "'$1' cannot be extracted via extract" >&2;;
-      esac
-    else
-      echo "extract: '$1' is not a valid file" >&2
-    fi
-      shift
-  done
-}
-# ls archives (inspired by `extract`)
-lsz() {
-  if [ $# -ne 1 ]
-  then
-      echo "lsz filename.[tar,tgz,gz,rar,zip,etc]"
-      return 1
-  fi
-  if [ -f $1 ] ; then
-    case $1 in
-      *.tar.bz2|*.tar.gz|*.tar|*.tbz2|*.tgz) tar tvf $1;;
-      *.rar)  unrar l $1;;
-      *.zip)  unzip -l $1;;
-      *)      echo "'$1' unrecognized." ;;
-    esac
-  else
-    echo "'$1' is not a valid file"
-  fi
-}
-# Creates an archive (*.tar.gz) from given directory.
-maketar() { tar cvzf "${1%%/}.tar.gz"  "${1%%/}/"; }
-# Create a ZIP archive of a file or folder.
-makezip() { zip -r "${1%%/}.zip" "$1" ; }
-#-------------------------------------------------------------
-# Calculator functions.
-#-------------------------------------------------------------
-# Calculate an expression e.g. calc 1+1.
-calc() {
-  echo "$@"|bc -l;
-}
-#-------------------------------------------------------------
-# cd.
-#-------------------------------------------------------------
-# cd = pushd, b = go backwards (popd), f = go forwards (kind of like "unpopd").
-#alias d='dirs'
-#alias b='pushd +1'
-#alias f='pushd -0'
-cd() {
-  if [ "$*" = "" ]; then
-    pushd $HOME >/dev/null
-  else
-    pushd "$*" >/dev/null
-  fi
-}
-# cd to the directory a symbolically linked file is in.
-cdlink() {
-  if [ "x$1" = "x" ] ; then
-    echo "Missing Arg"
-  elif [ -L "$1" ] ; then
-    link=`/bin/ls -l $1 | tr -s ' ' | cut -d' ' -f11`
-    if [ "x$link" = "x" ] ; then
-      echo "Failed to get link"
-      return
-    fi
-    dirName_=`dirname $link`
-    cd "$dirName_"
-  else
-    echo "$1 is not a symbolic link"
-  fi
-  return
-}
-# cd to the dir that a file is found in.
-cdff() {
-  filename=`find . -name $1 | grep -iv "Permission Denied" | head -1`
-  if [ "xx${filename}xx" != "xxxx" ] ; then
-    dirname=${filename%/*}
-    if [ -d $dirname ] ; then
-      cd $dirname
-    fi
-  fi
-}
-#-------------------------------------------------------------
-# Directory functions.
-#-------------------------------------------------------------
-# Jumps to a directory at any level below using globstar.
-jd() {
-  if [ -z $1 ]; then
-    echo "Usage: jd [directory]";
-    return 1
-  else
-    cd **/$@
-  fi
-}
-# Go up a specified number of directories.
-# If you pass no arguments, it just goes up one directory.
-# If you pass a numeric argument it will go up that number of directories.
-# If you pass a string argument, it will look for a parent directory with that name and go up to it.
-up() {
-  dir=""
-  if [ -z "$1" ]; then
-    dir=..
-  elif [[ $1 =~ ^[0-9]+$ ]]; then
-    x=0
-    while [ $x -lt ${1:-1} ]; do
-      dir=${dir}../
-      x=$(($x+1))
-    done
-  else
-    dir=${PWD%/$1/*}/$1
-  fi
-  cd "$dir";
-}
-#-------------------------------------------------------------
-# Disk functions.
-#-------------------------------------------------------------
-# Pretty-print of 'df' output.
-# Inspired by 'dfc' utility.
-mydf() {····
-  for fs ; do
-    if [ ! -d $fs ]; then
-      echo -e $fs" :No such file or directory" ; continue
-    fi
-    local info=( $(command df -P $fs | awk 'END{ print $2,$3,$5 }') )
-    local free=( $(command df -Pkh $fs | awk 'END{ print $4 }') )
-    local nbstars=$(( 20 * ${info[1]} / ${info[0]} ))
-    local out="["
-    for ((j=0;j<20;j++)); do
-      if [ ${j} -lt ${nbstars} ]; then
-        out=$out"*"
-      else
-        out=$out"-"
-      fi
-    done
-    out=${info[2]}" "$out"] ("$free" free on "$fs")"
-    echo -e $out
-  done
-}
-#-------------------------------------------------------------
-# Downloading functions.
-#-------------------------------------------------------------
-# More persistent wget for fetching files to a specific filename.
-wgettofile() {
-  [ $# -ne 2 ] && echo "usage: wgettofile <url> <filename>" && return 1
-  urltofetch=$1
-  fname="$2"
-  wget -O "$fname" $urltofetch
-}
-#-------------------------------------------------------------
-# Email functions.
-#-------------------------------------------------------------
-# Email me a short note.
-emailme() {
-  if [ $# -eq 0 ]; then
-    echo Usage: emailme text
-    return 1
-  fi
-  echo "$*" | mailx -s "$*" peter
-  echo "Sent email"
-}
-#-------------------------------------------------------------
-# File functions.
-#-------------------------------------------------------------
-# Backup file(s)
-filebackup() {
-  if [ $# -lt 1 ]; then
-    echo Please supply a file to backup
-    return 1
-  fi
-  date=`date +%Y%m%d-%H%M%S`
-  for i in "$@"
-  do
-    echo Backed up $i to $i.$date
-    cp $i $i.$date
-  done
-}
-# Output a text file with line numbers
-#
-# Overriding the newline-to-tab conversion (with the -d flag) and
-# replacing newlines with TAB-newline, maintaining the newline·
-# but indenting it. sed = will number the lines in the output,·
-# and the -s switch on paste will restore our whitespace keeping·
-# the line number justified to the left.
-filecatno() {
-  if [ $# == 0 ]; then
-    echo "No filename provided."
-  else
-    sed = "$1" | paste -s -d '\t\n' - -
-  fi
-}
-# Show all strings (ASCII & Unicode) in a file.
-filecatstr() { cat "$1" | tr -d "\0" | strings ; }
-# Changes the extension of all of the specified files in a directory.
-# It takes two arguments, first the original extension,·
-# then the extension to replace it with.·
-# For example
-#   filechgext html php
-filechgext() {
-  for file in *.$1 ; do mv "$file" "${file%.$1}.$2" ; done
-}
-# Find a file with pattern $1 in name and Execute $2 on it:
-fileexec() {·
-  find . -type f -iname '*'"${1:-}"'*' \
-    -exec ${2:-file} {} \;  ; }
-# Fast find, using globstar.
-filefind() {
-  ls -ltr **/$@
-}
-# Swap 2 filenames around, if they exist.
-fileswap() {
-  local TMPFILE=tmp.$$
-  [ $# -ne 2 ] && echo "Usage: fileswap file1 file2" && return 1
-#  [ $# -ne 2 ] && echo "fileswap: 2 arguments needed" && return 1
-  [ ! -e $1 ] && echo "fileswap: $1 does not exist" && return 1
-  [ ! -e $2 ] && echo "fileswap: $2 does not exist" && return 1
-  mv "$1" $TMPFILE
-  mv "$2" "$1"
-  mv $TMPFILE "$2"
-}
-# Moves file to ~/.Trash (use instead of rm).
-filetrash() {
-  if [ $# -eq 0 ]; then
-    echo Usage: filetrash FILE...
-    return 1
-  fi
-  local DATE=$(date +%Y%m%d)
-  [ -d "${HOME}/.Trash/${DATE}" ] || mkdir -p ${HOME}/.Trash/${DATE}
-  for FILE in "$@"
-  do
-    mv "${FILE}" "${HOME}/.Trash/${DATE}"
-    echo "${FILE} trashed!"
-  done
-}
-# Overwrite a file with zeroes.
-filezero() {
-  case "$1" in
-    "")     echo "Usage: filezero "
-            return -1;
-  esac
-  filesize=`wc -c  "$1" | awk '{print $1}'`
-  dd if=/dev/zero of=$1 count=$filesize bs=1
-}
-#-------------------------------------------------------------
-# Firewall functions.
-#-------------------------------------------------------------
-# Ban IP
-ban() {
-  if [ "`id -u`" == "0" ] ; then
-    iptables -A INPUT -s $1 -j DROP
-  else
-    sudo iptables -A INPUT -s $1 -j DROP
-  fi
-}
-#-------------------------------------------------------------
-# Grep Find Search functions.
-#-------------------------------------------------------------
-# Find a file with a pattern in name:
-ff() { find . -type f -iname '*'"$*"'*' -ls ; }
-# Find a file whose name starts with a given string.
-ffs() { /usr/bin/find . -name "$@"'*' ; }
-# Find a file whose name ends with a given string.
-ffe() { /usr/bin/find . -name '*'"$@" ; }
-# Find files larger than a certain size (in bytes).
-ffbigger() { find . -type f 2>/dev/null | xargs \du -a -b 2>/dev/null | awk "{ if ( \$1 > $@) print \$0 }" | sort -hr; }
-# Find a pattern in a set of files and highlight them:
-# (needs a recent version of egrep).
-findstr() {
-  OPTIND=1
-  local mycase=""
-  local usage="findstr: find string in files.
-Usage: grepstr [-i] \"pattern\" [\"filename pattern\"] "
-  while getopts :it opt
-  do
-    case "$opt" in
-      i) mycase="-i " ;;
-      *) echo "$usage"; return ;;
-    esac
-  done
-  shift $(( $OPTIND - 1 ))
-  if [ "$#" -lt 1 ]; then
-    echo "$usage"
-    return;
-  fi
-  find . -type f -name "${2:-*}" -print0 | \
-    xargs -0 egrep --color=always -sn ${case} "$1" 2>&- | more
-}
-# Search for a word in the Unix word list.
-word() { /bin/grep ^"$@"$ /usr/share/dict/words ; }
-# Search for a word in the Unix word list that ends with the chars.
-wordstarts() { /bin/grep ^"$@" /usr/share/dict/words ; }
-# Search for a word in the Unix word list that ends with the chars.
-wordends() { /bin/grep "$@"$ /usr/share/dict/words ; }
-#-------------------------------------------------------------
-# Info functions.
-#-------------------------------------------------------------
-# Get current host related info.
-ii() {
-  echo -e "\nYou are logged on ${BRed}$HOST"
-  echo -e "\n${BRed}Additionnal information:$NC " ; uname -a
-  echo -e "\n${BRed}Users logged on:$NC " ; w -hs |
-    cut -d " " -f1 | sort | uniq
-  echo -e "\n${BRed}Current date :$NC " ; date
-  echo -e "\n${BRed}Machine stats :$NC " ; uptime
-  echo -e "\n${BRed}Memory stats :$NC " ; free
-  echo -e "\n${BRed}Diskspace :$NC " ; mydf / $HOME
-  echo -e "\n${BRed}Local IP Address :$NC" ; myip
-  echo -e "\n${BRed}Open connections :$NC "; netstat -pan --inet;
-  echo
-}
-#-------------------------------------------------------------
-# Misc functions.
-#-------------------------------------------------------------
-# Waits for the user to press a y or n.
-#
-# Example:
-#        if ask "Kill process $pid <$pname> with signal $sig?"
-#            then kill $sig $pid
-#        fi
-ask() {
-  echo -n "$@" '[y/n] ' ; read ans
-  case "$ans" in
-    y*|Y*) return 0 ;;
-    *) return 1 ;;
-  esac
-}
-# Repeat n times command.
-#
-# Example:
-#   repeat 10 ls
-repeat() {
-  local i max
-  max=$1; shift;
-  for ((i=1; i <= max ; i++)); do  # --> C-like syntax
-    eval "$@";
-  done
-}
-# Do something very quietly.
-runquiet() {
- ( $@ ) >/dev/null 2>/dev/null
-}
-#-------------------------------------------------------------
-# Network functions.
-#-------------------------------------------------------------
-# myIP address
-ipall() {
-  ifconfig lo | grep 'inet ' | sed -e 's/:/ /' | awk '{print "lo: " $2 " " $3 " " $4 " " $5 " " $6}'
-  ifconfig em1 | grep 'inet ' | sed -e 's/:/ /' | awk '{print "em1 (IPv4): " $2 " " $3 " " $4 " " $5 " " $6}'
-  ifconfig em1 | grep 'inet6 ' | sed -e 's/ / /' | awk '{print "em1 (IPv6): " $2 " " $3 " " $4 " " $5 " " $6}'
-  ifconfig em2 | grep 'inet ' | sed -e 's/:/ /' | awk '{print "em2 (IPv4): " $2 " " $3 " " $4 " " $5 " " $6}'
-  ifconfig em2 | grep 'inet6 ' | sed -e 's/ / /' | awk '{print "em2 (IPv6): " $2 " " $3 " " $4 " " $5 " " $6}'
-}
-# Get IP adress on ethernet.
-myip() {
-#    MY_IP=$(/sbin/ifconfig eth0 | awk '/inet/ { print $2 } ' |
-  MY_IP=$(/sbin/ifconfig em1 | awk '/inet/ { print $2 } ' |
-  sed -e s/addr://)
-  echo ${MY_IP:-"Not connected"}
-}
-getip() {
-  for each in $@; do
-    echo $each
-    echo "nslookup:"
-    nslookup $each | grep Address: | grep -v '#' | egrep -o '([0-9]+\.){3}[0-9]+'
-    echo "ping:"
-    ping -c1 -t1 $each | egrep -o '([0-9]+\.){3}[0-9]+' | head -n1
-  done
-}
-#-------------------------------------------------------------
-# Process functions.
-#-------------------------------------------------------------
-psnice() {
-  if ! [ -z "$1" ]; then
-    # Take a parameter pid.
-    ionice -c3 -p$1 ; renice -n 19 -p $1
-  else
-    # If no parameter is nice the current pid (bash).
-    ionice -c3 -p$$ ; renice -n 19 -p $$
-  fi
-}
-#-------------------------------------------------------------
-# String functions.
-#-------------------------------------------------------------
-# substring word start [length]
-substring() {
-  if [ $# -lt 2 ]; then
-    echo "Usage: substring word start [length]"
-    return 1
-  fi
-  if [ -z $3 ]; then
-    echo ${1:$2}
-  else
-    echo ${1:$2:$3}
-  fi
-}
-# Get length of string.
-strlen() {
-  if [ $# -ne 1 ]; then
-    echo "Usage: length word"
-    return 1
-  fi
-  echo ${#1}
-}
-# Convert string to upper-case.
-strupper() {
-  if [ $# -lt 1 ]; then
-    echo "Usage: upper word"
-    return 1
-  fi
-  echo ${@^^}
-}
-# Convert string to lower-case.
-strlower() {
-  if [ $# -lt 1 ]; then
-    echo "Usage: lower word"
-    return 1
-  fi
-  echo ${@,,}
-}
-# Replace part of string with another.
-strreplace() {
-  if [ $# -ne 3 ]; then
-    echo "Usage: replace string substring replacement"
-    return 1
-  fi
-  echo ${1/$2/$3}
-}
-# Replace all parts of a string with another.
-strreplaceall() {
-  if [ $# -ne 3 ]; then
-    echo "Usage: replace string substring replacement"
-    return 1
-  fi
-  echo ${1//$2/$3}
-}
-# Find index of specified string.
-strindex() {
-  if [ $# -ne 2 ]; then
-    echo "Usage: index string substring"
-    return 1
-  fi
-  expr index $1 $2
-}
-strquote() { echo "$@" | /bin/sed 's/^/"/;s/$/"/' ; }
-# Surround string with whatever is given as 2nd param.
-#
-# Example:
-#   strsurround abc 123
-#   strsurround abc \"
-#   strsurround abc \\\\
-strsurround() {
-  if [ $# -ne 2 ]; then
-    echo Usage: surround string surround-with e.g. strsurround hello \\\"
-    return 1
-  fi
-  echo $1 | sed "s/^/$2/;s/$/$2/" ;
-}
-#-------------------------------------------------------------
-# Text functions.
-#-------------------------------------------------------------
-# Truncate lines longer than 80 characters (for use in pipes).
-#alias cut80='/usr/bin/cut -c 1-80'
-#cut80() { echo "$@" | cut -c 1-80 ; }
-# Surround lines with quotes (useful in pipes).
-quote() { echo "$@" | /bin/sed 's/^/"/;s/$/"/' ; }
-#-------------------------------------------------------------
-# USB functions.
-#-------------------------------------------------------------
-# Need to figure out which drive your usb is assigned? Functions work the same way as an alias. Simply copy the line into your .profile/.bashrc file. Then type: myusb
-myusb() { usb_array=();while read -r -d $'\n'; do usb_array+=("$REPLY"); done < <(find /dev/disk/by-path/ -type l -iname \*usb\*scsi\* -not -iname \*usb\*scsi\*part* -print0 | xargs -0 -iD readlink -f D | cut -c 8) && for usb in "${usb_array[@]}"; do echo "USB drive assigned to sd$usb"; done; }
-</file>