A lot of the answers here helped point me in the right direction, however none were suitable for me, so I am posting my solution.
I have Windows 7, which comes with PowerShell built-in. Here is the script I used to find/replace all instances of text in a file:
powershell -Command "(gc myFile.txt) -replace 'foo', 'bar' | Out-File -encoding ASCII myFile.txt"
To explain it:
powershell
starts up powershell.exe, which is included in Windows 7
-Command "... "
is a command line arg for powershell.exe containing the command to run
(gc myFile.txt)
reads the content of myFile.txt
(gc
is short for the Get-Content
command)
-replace 'foo', 'bar'
simply runs the replace command to replace foo
with bar
| Out-File myFile.txt
pipes the output to the file myFile.txt
-encoding ASCII
prevents transcribing the output file to unicode, as the comments point out
Powershell.exe should be part of your PATH statement already, but if not you can add it. The location of it on my machine is C:\WINDOWS\system32\WindowsPowerShell\v1.0
Update
Apparently modern windows systems have PowerShell built in allowing you to access this directly using
(Get-Content myFile.txt) -replace 'foo', 'bar' | Out-File -encoding ASCII myFile.txt
Bash Space-Separated (e.g., --option argument
)
cat >/tmp/demo-space-separated.sh <<'EOF'
#!/bin/bash
POSITIONAL=()
while [[ $# -gt 0 ]]; do
key="$1"
case $key in
-e|--extension)
EXTENSION="$2"
shift # past argument
shift # past value
;;
-s|--searchpath)
SEARCHPATH="$2"
shift # past argument
shift # past value
;;
-l|--lib)
LIBPATH="$2"
shift # past argument
shift # past value
;;
--default)
DEFAULT=YES
shift # past argument
;;
*) # unknown option
POSITIONAL+=("$1") # save it in an array for later
shift # past argument
;;
esac
done
set -- "${POSITIONAL[@]}" # restore positional parameters
echo "FILE EXTENSION = ${EXTENSION}"
echo "SEARCH PATH = ${SEARCHPATH}"
echo "LIBRARY PATH = ${LIBPATH}"
echo "DEFAULT = ${DEFAULT}"
echo "Number files in SEARCH PATH with EXTENSION:" $(ls -1 "${SEARCHPATH}"/*."${EXTENSION}" | wc -l)
if [[ -n $1 ]]; then
echo "Last line of file specified as non-opt/last argument:"
tail -1 "$1"
fi
EOF
chmod +x /tmp/demo-space-separated.sh
/tmp/demo-space-separated.sh -e conf -s /etc -l /usr/lib /etc/hosts
Output from copy-pasting the block above
FILE EXTENSION = conf
SEARCH PATH = /etc
LIBRARY PATH = /usr/lib
DEFAULT =
Number files in SEARCH PATH with EXTENSION: 14
Last line of file specified as non-opt/last argument:
#93.184.216.34 example.com
Usage
demo-space-separated.sh -e conf -s /etc -l /usr/lib /etc/hosts
Bash Equals-Separated (e.g., --option=argument
)
cat >/tmp/demo-equals-separated.sh <<'EOF'
#!/bin/bash
for i in "$@"; do
case $i in
-e=*|--extension=*)
EXTENSION="${i#*=}"
shift # past argument=value
;;
-s=*|--searchpath=*)
SEARCHPATH="${i#*=}"
shift # past argument=value
;;
-l=*|--lib=*)
LIBPATH="${i#*=}"
shift # past argument=value
;;
--default)
DEFAULT=YES
shift # past argument with no value
;;
*)
# unknown option
;;
esac
done
echo "FILE EXTENSION = ${EXTENSION}"
echo "SEARCH PATH = ${SEARCHPATH}"
echo "LIBRARY PATH = ${LIBPATH}"
echo "DEFAULT = ${DEFAULT}"
echo "Number files in SEARCH PATH with EXTENSION:" $(ls -1 "${SEARCHPATH}"/*."${EXTENSION}" | wc -l)
if [[ -n $1 ]]; then
echo "Last line of file specified as non-opt/last argument:"
tail -1 $1
fi
EOF
chmod +x /tmp/demo-equals-separated.sh
/tmp/demo-equals-separated.sh -e=conf -s=/etc -l=/usr/lib /etc/hosts
Output from copy-pasting the block above
FILE EXTENSION = conf
SEARCH PATH = /etc
LIBRARY PATH = /usr/lib
DEFAULT =
Number files in SEARCH PATH with EXTENSION: 14
Last line of file specified as non-opt/last argument:
#93.184.216.34 example.com
Usage
demo-equals-separated.sh -e=conf -s=/etc -l=/usr/lib /etc/hosts
To better understand ${i#*=}
search for "Substring Removal" in this guide. It is functionally equivalent to `sed 's/[^=]*=//' <<< "$i"`
which calls a needless subprocess or `echo "$i" | sed 's/[^=]*=//'`
which calls two needless subprocesses.
Using bash with getopt[s]
getopt(1) limitations (older, relatively-recent getopt
versions):
- can't handle arguments that are empty strings
- can't handle arguments with embedded whitespace
More recent getopt
versions don't have these limitations. For more information, see these docs.
POSIX getopts
Additionally, the POSIX shell and others offer getopts
which doen't have these limitations. I've included a simplistic getopts
example.
cat >/tmp/demo-getopts.sh <<'EOF'
#!/bin/sh
# A POSIX variable
OPTIND=1 # Reset in case getopts has been used previously in the shell.
# Initialize our own variables:
output_file=""
verbose=0
while getopts "h?vf:" opt; do
case "$opt" in
h|\?)
show_help
exit 0
;;
v) verbose=1
;;
f) output_file=$OPTARG
;;
esac
done
shift $((OPTIND-1))
[ "${1:-}" = "--" ] && shift
echo "verbose=$verbose, output_file='$output_file', Leftovers: $@"
EOF
chmod +x /tmp/demo-getopts.sh
/tmp/demo-getopts.sh -vf /etc/hosts foo bar
Output from copy-pasting the block above
verbose=1, output_file='/etc/hosts', Leftovers: foo bar
Usage
demo-getopts.sh -vf /etc/hosts foo bar
The advantages of getopts
are:
- It's more portable, and will work in other shells like
dash
.
- It can handle multiple single options like
-vf filename
in the typical Unix way, automatically.
The disadvantage of getopts
is that it can only handle short options (-h
, not --help
) without additional code.
There is a getopts tutorial which explains what all of the syntax and variables mean. In bash, there is also help getopts
, which might be informative.
Best Answer
After lots of research, I've come up with this answer, and I'm hereby putting it here as an answer for my own question, for reference:
Make sure that "Enable access for assistive devices" is checked in System Preferences>>Universal Access. It is required for the AppleScript to work. You may have to reboot after this change (it doesn't work otherwise on Mac OS X Server 10.4).
Create a R/W DMG. It must be larger than the result will be. In this example, the bash variable "size" contains the size in Kb and the contents of the folder in the "source" bash variable will be copied into the DMG:
Mount the disk image, and store the device name (you might want to use sleep for a few seconds after this operation):
Store the background picture (in PNG format) in a folder called ".background" in the DMG, and store its name in the "backgroundPictureName" variable.
Use AppleScript to set the visual styles (name of .app must be in bash variable "applicationName", use variables for the other properties as needed):
Finialize the DMG by setting permissions properly, compressing and releasing it:
On Snow Leopard, the above applescript will not set the icon position correctly - it seems to be a Snow Leopard bug. One workaround is to simply call close/open after setting the icons, i.e.: