In Git bash under Windows when I run echo $PATH command, I'm getting the following output:
c/Windows/System32:/c/Python27:/c/Python27/Scripts:c/HashiCorp/Vagrant/bin:/c/Program Files (x86)/GNU/GnuPG/pub:/c/Program Files (x86)/Private Shell:/c/Program Files (x86)/OpenSSH/bin:/c/HashiCorp/Vagrant/bin:/c/Program Files/Common Files/Intel/WirelessCommon/:/c/Program Files/Boot2Docker for Windows:c/Windows/System32:/c/Python27:/c/Python27/Scripts
What I need to do is extracting whole POSIX path, like /c/Program Files/Boot2Docker for Windows to variable in bash script, identifying it by Boot2Docker for Windows phrase.
echo $PATH | grep -o "[^:]*Boot2Docker for Windows[^:]*"
returns:
/c/Program Files/Boot2Docker for Windows
Using BASH regex:
[[ $PATH =~ ([^:]*"Boot2Docker for Windows"[^:]*) ]] && echo "${BASH_REMATCH[1]}"
/c/Program Files/Boot2Docker for Windows
Using read with a custom IFS.
b2ddir=
IFS=: read -a a <<<"$WPATH"
for p in "${a[#]}"; do
case "$p" in
*"Boot2Docker for Windows"*)
b2ddir=$p
break
;;
esac
done
declare -p b2ddir
Related
I'm trying to loop through files in a directory, where the directory is passed through as an argument. I currently have the following script saved in test.sh:
#!/bin/bash
for filename in "$1"/*; do
echo "File:"
echo $filename
done
And I am running the above using:
sh test.sh path/to/loop/over
However, the above doesn't output the files at the directory path/to/loop/over, it instead outputs:
File:
path/to/loop/over/*
I'm guessing it's interpreting path/to/loop/over/* as a string and not a directory. My expected output is the following:
File:
foo.txt
File:
bar.txt
Where foo.txt and bar.txt are files in the path/to/loop/over/ directory. I found this answer which suggested to add a /* after the $1, however, this doesn't seem to help (neither do these suggestions)
Iterate over content of directory
Compatible answer (not only bash)
As this question is tagged shell, there is a POSIX compatible way:
#!/bin/sh
for file in "$1"/* ;do
[ -f "$file" ] && echo "Process '$file'."
done
Will be enough (work with filenames containing spaces):
$ myscript.sh /path/to/dir
Process '/path/to/dir/foo'.
Process '/path/to/dir/bar'.
Process '/path/to/dir/foo bar'.
This work well by using any posix shell. Tested with bash, ksh, dash, zsh and busybox sh.
#!/bin/sh
cd "$1" || exit 1
for file in * ;do
[ -f "$file" ] && echo "Process '$file'."
done
This version won't print path:
$ myscript.sh /path/to/dir
Process 'foo'.
Process 'bar'.
Process 'foo bar'.
Some bash ways
Introduction
I don't like to use shopt when not needed... (This change standard
bash behaviours and make script less readables).
There is an elegant way for doing this by using standard bash, without requirement of shopt.
Of course, previous answer work fine under bash, but. There are some
interresting way for making your script more powerfull, flexible, pretty, detailed...
Sample
#!/bin/bash
die() { echo >&2 "$0 ERROR: $#";exit 1;} # Emergency exit function
[ "$1" ] || die "Argument missing." # Exit unless argument submitted
[ -d "$1" ] || die "Arg '$1' is not a directory." # Exit if argument is not dir
cd "$1" || die "Can't access '$1'." # Exit unless access dir.
files=(*) # All files names in array $files
[ -f "$files" ] || die "No files found." # Exit if no files found
for file in "${files[#]}";do # foreach file:
echo Process "$file" # Process file
done
Explanation: considering globbing vs real files
When doing:
files=(/path/to/dir/*)
variable $files becomes an array containing all files contained under /path/to/dir/:
declare -p files
declare -a files=([0]="/path/to/dir/bar" [1]="/path/to/dir/baz" [2]="/path/to/dir/foo")
But if nothing match glob pattern, star won't be replaced and array become:
declare -p files
declare -a files=([0]="/path/to/dir/*")
From there. looking for $files is like looking for ${files[0]} ie: first field in array. So
[ -f "$files" ] || die "No files found."
will execute die function unless first field of array files is a file ([ -e "$files" ] to check for existing entry, [ -d "$files" ] to check for existing directory, ans so on... see man bash or help test).
But you could do replace this filesystem test by some string based test, like:
[ "$files" = "/path/to/dir/*" ] && die "No files found."
or, using array length:
((${#files[#]}==1)) && [ "${files##*/}" = "*" ] && die "No files found."
Dropping paths by using Parameter expansion:
For suppressing path from filenames, instead of cd $path you could do:
targetPath=/path/to/dir
files=($targetPath/*)
[ -f "$files" ] || die "No files found."
Then:
declare -p files
declare -a files=([0]="/path/to/dir/bar" [1]="/path/to/dir/baz" [2]="/path/to/dir/foo")
You could
printf 'File: %s\n' ${files[#]#$targetPath/}
File: bar
File: baz
File: foo
This would happen if the directory is empty, or misspelled. The shell (in its default configuration) simply doesn't expand a wildcard if it has no matches. (You can control this in Bash with shopt -s nullglob; with this option, wildcards which don't match anything are simply removed.)
You can verify this easily for yourself. In a directory with four files,
sh$ echo *
a file or two
sh$ echo [ot]*
or two
sh$ echo n*
n*
And in Bash,
bash$ echo n*
n*
bash$ shopt -s nullglob
bash$ echo n*
I'm guessing you are confused about how the current working directory affects the resolution of directory names; maybe read Difference between ./ and ~/
I'm trying to add a conditional to my .zshrc file that will initialize some config stuff that I only want to happen if I'm in Windows Subsystem for Linux. I tried this but no luck:
if [ "$('cmd.exe /c "systeminfo" | grep "^OS Name"')" =~ "Windows" ]; then
echo "windows baby!"
fi
Which gives:
no such file or directory: cmd.exe /c "systeminfo" | grep "^OS Name"
...but that command works if I type it directly in the shell.
Any ideas?
Using uname -r does the trick
According to https://github.com/microsoft/WSL/issues/423#issuecomment-608236476, if you use
uname -r | sed -n 's/.*\( *Microsoft *\).*/\1/ip'
You'll get output as "Microsoft" in case it is WSL. Otherwise, you should get no output.
So you can use something like
if [ $(uname -r | sed -n 's/.*\( *Microsoft *\).*/\1/ip') ];
then
echo "This is Windows WSL baby!"
else
echo "Not Windows"
fi
I am attempting to write a bash script that changes directory and then runs an existing script in the new working directory.
This is what I have so far:
#!/bin/bash
cd /path/to/a/folder
./scriptname
scriptname is an executable file that exists in /path/to/a/folder - and (needless to say), I do have permission to run that script.
However, when I run this mind numbingly simple script (above), I get the response:
scriptname: No such file or directory
What am I missing?! the commands work as expected when entered at the CLI, so I am at a loss to explain the error message. How do I fix this?
Looking at your script makes me think that the script you want to launch a script which is locate in the initial directory. Since you change you directory before executing it won't work.
I suggest the following modified script:
#!/bin/bash
SCRIPT_DIR=$PWD
cd /path/to/a/folder
$SCRIPT_DIR/scriptname
cd /path/to/a/folder
pwd
ls
./scriptname
which'll show you what it thinks it's doing.
I usually have something like this in my useful script directory:
#!/bin/bash
# Provide usage information if not arguments were supplied
if [[ "$#" -le 0 ]]; then
echo "Usage: $0 <executable> [<argument>...]" >&2
exit 1
fi
# Get the executable by removing the last slash and anything before it
X="${1##*/}"
# Get the directory by removing the executable name
D="${1%$X}"
# Check if the directory exists
if [[ -d "$D" ]]; then
# If it does, cd into it
cd "$D"
else
if [[ "$D" ]]; then
# Complain if a directory was specified, but does not exist
echo "Directory '$D' does not exist" >&2
exit 1
fi
fi
# Check if the executable is, well, executable
if [[ -x "$X" ]]; then
# Run the executable in its directory with the supplied arguments
exec ./"$X" "${#:2}"
else
# Complain if the executable is not a valid
echo "Executable '$X' does not exist in '$D'" >&2
exit 1
fi
Usage:
$ cdexec
Usage: /home/archon/bin/cdexec <executable> [<argument>...]
$ cdexec /bin/ls ls
ls
$ cdexec /bin/xxx/ls ls
Directory '/bin/xxx/' does not exist
$ cdexec /ls ls
Executable 'ls' does not exist in '/'
One source of such error messages under those conditions is a broken symlink.
However, you say the script works when run from the command line. I would also check to see whether the directory is a symlink that's doing something other than what you expect.
Does it work if you call it in your script with the full path instead of using cd?
#!/bin/bash
/path/to/a/folder/scriptname
What about when called that way from the command line?
Is it possible to find out the full path to the script that is currently executing in KornShell (ksh)?
i.e. if my script is in /opt/scripts/myscript.ksh, can I programmatically inside that script discover /opt/scripts/myscript.ksh ?
Thanks,
You could use:
## __SCRIPTNAME - name of the script without the path
##
typeset -r __SCRIPTNAME="${0##*/}"
## __SCRIPTDIR - path of the script (as entered by the user!)
##
__SCRIPTDIR="${0%/*}"
## __REAL_SCRIPTDIR - path of the script (real path, maybe a link)
##
__REAL_SCRIPTDIR=$( cd -P -- "$(dirname -- "$(command -v -- "$0")")" && pwd -P )
In korn shell, all of these $0 solutions fail if you are sourcing in the script in question. The correct way to get what you want is to use $_
$ cat bar
echo dollar under is $_
echo dollar zero is $0
$ ./bar
dollar under is ./bar
dollar zero is ./bar
$ . ./bar
dollar under is bar
dollar zero is -ksh
Notice the last line there? Use $_. At least in Korn. YMMV in bash, csh, et al..
Well it took me a while but this one is so simple it screams.
_SCRIPTDIR=$(cd $(dirname $0);echo $PWD)
since the CD operates in the spawned shell with $() it doesn't affect the current script.
How the script was called is stored in the variable $0. You can use readlink to get the absolute file name:
readlink -f "$0"
The variable $RPATH contains the relative path to the real file or the real path for a real file.
CURPATH=$( cd -P -- "$(dirname -- "$(command -v -- "$0")")" && pwd -P )
CURLOC=$CURPATH/`basename $0`
if [ `ls -dl $CURLOC |grep -c "^l" 2>/dev/null` -ne 0 ];then
ROFFSET=`ls -ld $CURLOC|cut -d ">" -f2 2>/dev/null`
RPATH=`ls -ld $CURLOC/$ROFFSET 2>/dev/null`
else
RPATH=$CURLOC
fi
echo $RPATH
This is what I did:
if [[ $0 != "/"* ]]; then
DIR=`pwd`/`dirname $0`
else
DIR=`dirname $0`
fi
readlink -f would be the best if it was portable, because it resolves every links found for both directories and files.
On mac os x there is no readlink -f (except maybe via macports), so you can only use readlink to get the destination of a specific symbolic link file.
The $(cd -P ... pwd -P) technique is nice but only works to resolve links for directories leading to the script, it doesn't work if the script itself is a symlink
Also, one case that wasn't mentioned : when you launch a script by passing it as an argument to a shell (/bin/sh /path/to/myscript.sh), $0 is not usable in this case
I took a look to mysql "binaries", many of them are actually shell scripts ; and now i understand why they ask for a --basedir option or need to be launched from a specific working directory ; this is because there is no good solution to locate the targeted script
This works also, although it won't give the "true" path if it's a link. It's simpler, but less exact.
SCRIPT_PATH="$(whence ${0})"
Try which command.
which scriptname
will give you the full qualified name of the script along with its absolute path
I upgraded the Edward Staudt's answer, to be able to deal with absolute-path symbolic links, and with chains of links too.
DZERO=$0
while true; do
echo "Trying to find real dir for script $DZERO"
CPATH=$( cd -P -- "$(dirname -- "$(command -v -- "$DZERO")")" && pwd -P )
CFILE=$CPATH/`basename $DZERO`
if [ `ls -dl $CFILE | grep -c "^l" 2>/dev/null` -eq 0 ];then
break
fi
LNKTO=`ls -ld $CFILE | cut -d ">" -f2 | tr -d " " 2>/dev/null`
DZERO=`cd $CPATH ; command -v $LNKTO`
done
Ugly, but works...
After run this, the path is $CPATH and the file is $CFILE
Try using this:
dir = $(dirname $0)
Using $_ provides the last command.
>source my_script
Works if I issue the command twice:
>source my_script
>source my_script
If I use a different sequence of commands:
>who
>source my_script
The $_ variable returns "who"
I have a bash script that creates a Subversion patch file for the current directory. I want to modify it to zip the produced file, if -z is given as an argument to the script.
Here's the relevant part:
zipped=''
zipcommand='>'
if [ "$1" = "-z" ]
then
zipped='zipped '
filename="${filename}.zip"
zipcommand='| zip >'
fi
echo "Creating ${zipped}patch file $filename..."
svn diff $zipcommand $filename
This doesn't work because it passes the | or > contained in $zipcommand as an argument to svn.
I can easily work around this, but the question is whether it's ever possible to use these kinds of operators when they're contained in variables.
Thanks!
I would do something like this (use bash -c or eval):
zipped=''
zipcommand='>'
if [ "$1" = "-z" ]
then
zipped='zipped '
filename="${filename}.zip"
zipcommand='| zip -#'
fi
echo "Creating ${zipped}patch file $filename..."
eval "svn diff $zipcommand $filename"
# this also works:
# bash -c "svn diff $zipcommand $filename"
This appears to work, but my version of zip (Mac OS X) required that i change the line:
zipcommand='| zip -#'
to
zipcommand='| zip - - >'
Edit: incorporated #DanielBungert's suggestion to use eval
eval is what you are looking for.
# eval 'printf "foo\nbar" | grep bar'
bar
Be careful with quote characters on that.
Or you should try zsh shell whic allows to define global aliases, e.g.:
alias -g L='| less'
alias -g S='| sort'
alias -g U='| uniq -c'
Then use this command (which is somewhat cryptic for the ones who took a look from behind ;-) )
./somecommand.sh S U L
HTH
Open a new file handle on either a process substitution to handle the compression or on the named file. Then redirect the output of svn diff to that file handle.
if [ "$1" = "-z" ]; then
zipped='zipped '
filename=$filename.zip
exec 3> >(zip > "$filename")
else
exec 3> "$filename"
fi
echo "Creating ${zipped}patch file $filename"
svn diff >&3