I have the following to process a file:
$ vim file2
define(add2, `eval($1+$2)')
Adding 2+4=add2(2,4)
And to run:
$ m4 file
Adding 2+4=6
Is there a way to run m4 with the file contents inline? For example something like:
$ m4 <inline>
define(add2, `eval($1+$2)')
Adding 2+4=add2(2,4)
<ctrl-d>
# Adding 2+4=6
How could that be done?
One option is to the 'interactive mode':
-e, --interactive
unbuffer output, ignore interrupts
In which case you can do:
IM-MM:DD_Objects david$ m4 -e
define(add2, `eval($1+$2)')
Adding 2+4=add2(2,4)
Adding 2+4=6
Related
When I use any command with sudo the environment variables are not there. For example after setting HTTP_PROXY the command wget works fine without sudo. However if I type sudo wget it says it can't bypass the proxy setting.
First you need to export HTTP_PROXY. Second, you need to read man sudo, and look at the -E flag. This works:
$ export HTTP_PROXY=foof
$ sudo -E bash -c 'echo $HTTP_PROXY'
Here is the quote from the man page:
-E, --preserve-env
Indicates to the security policy that the user wishes to preserve their
existing environment variables. The security policy may return an error
if the user does not have permission to preserve the environment.
The trick is to add environment variables to sudoers file via sudo visudo command and add these lines:
Defaults env_keep += "ftp_proxy http_proxy https_proxy no_proxy"
taken from ArchLinux wiki.
For Ubuntu 14, you need to specify in separate lines as it returns the errors for multi-variable lines:
Defaults env_keep += "http_proxy"
Defaults env_keep += "https_proxy"
Defaults env_keep += "HTTP_PROXY"
Defaults env_keep += "HTTPS_PROXY"
For individual variables you want to make available on a one off basis you can make it part of the command.
sudo http_proxy=$http_proxy wget "http://stackoverflow.com"
You can also combine the two env_keep statements in Ahmed Aswani's answer into a single statement like this:
Defaults env_keep += "http_proxy https_proxy"
You should also consider specifying env_keep for only a single command like this:
Defaults!/bin/[your_command] env_keep += "http_proxy https_proxy"
A simple wrapper function (or in-line for loop)
I came up with a unique solution because:
sudo -E "$#" was leaking variables that was causing problems for my command
sudo VAR1="$VAR1" ... VAR42="$VAR42" "$#" was long and ugly in my case
demo.sh
#!/bin/bash
function sudo_exports(){
eval sudo $(for x in $_EXPORTS; do printf '%q=%q ' "$x" "${!x}"; done;) "$#"
}
# create a test script to call as sudo
echo 'echo Forty-Two is $VAR42' > sudo_test.sh
chmod +x sudo_test.sh
export VAR42="The Answer to the Ultimate Question of Life, The Universe, and Everything."
export _EXPORTS="_EXPORTS VAR1 VAR2 VAR3 VAR4 VAR5 VAR6 VAR7 VAR8 VAR9 VAR10 VAR11 VAR12 VAR13 VAR14 VAR15 VAR16 VAR17 VAR18 VAR19 VAR20 VAR21 VAR22 VAR23 VAR24 VAR25 VAR26 VAR27 VAR28 VAR29 VAR30 VAR31 VAR32 VAR33 VAR34 VAR35 VAR36 VAR37 VAR38 VAR39 VAR40 VAR41 VAR42"
# clean function style
sudo_exports ./sudo_test.sh
# or just use the content of the function
eval sudo $(for x in $_EXPORTS; do printf '%q=%q ' "$x" "${!x}"; done;) ./sudo_test.sh
Result
$ ./demo.sh
Forty-Two is The Answer to the Ultimate Question of Life, The Universe, and Everything.
Forty-Two is The Answer to the Ultimate Question of Life, The Universe, and Everything.
How?
This is made possible by a feature of the bash builtin printf. The %q produces a shell quoted string. Unlike the parameter expansion in bash 4.4, this works in bash versions < 4.0
Add code snippets to /etc/sudoers.d
Don't know if this is available in all distros, but in Debian-based distros, there is a line at or near the tail of the /etc/sudoers file that includes the folder /etc/sudoers.d. Herein, one may add code "snippets" that modify sudo's configuration. Specifically, they allow control over all environment variables used in sudo.
As with /etc/sudoers, these "code snippets" should be edited using visudo. You can start by reading the README file, which is also a handy place for keeping any notes you care to make:
$ sudo visudo -f /etc/sudoers.d/README
# files for your snippets may be created/edited like so:
$ sudo visudo -f /etc/sudoers.d/20_mysnippets
Read the "Command Environment" section of 'man 5 sudoers'
Perhaps the most informative documentation on environment configuration in sudo is found in the Command environment section of man 5 sudoers. Here, we learn that a sudoers environment variables that are blocked by default may be "whitelisted" using the env_check or env_keep options; e.g.
Defaults env_keep += "http_proxy HTTP_PROXY"
Defaults env_keep += "https_proxy HTTPS_PROXY"
Defaults env_keep += "ftp_proxy FTP_PROXY"
And so, in the OP's case, we may "pass" the sudoer's environment variables as follows:
$ sudo visudo -f /etc/sudoers.d/10_myenvwlist
# opens the default editor for entry of the following lines:
Defaults env_keep += "http_proxy HTTP_PROXY"
Defaults env_keep += "https_proxy HTTPS_PROXY"
# and any others deemed useful/necessary
# Save the file, close the editor, and you are done!
Get your bearings from '# sudo -V'
The OP presumably discovered the missing environment variable in sudo by trial-and-error. However, it is possible to be proactive: A listing of all environment variables, and their allowed or denied status is available (and unique to each host) from the root prompt as follows:
# sudo -V
...
Environment variables to check for safety:
...
Environment variables to remove:
...
Environment variables to preserve:
...
Note that once an environment variable is "whitelisted" as above, it will appear in subsequent listings of sudo -V under the "preserve" listing.
If you have the need to keep the environment variables in a script you can put your command in a here document like this. Especially if you have lots of variables to set things look tidy this way.
# prepare a script e.g. for running maven
runmaven=/tmp/runmaven$$
# create the script with a here document
cat << EOF > $runmaven
#!/bin/bash
# run the maven clean with environment variables set
export ANT_HOME=/usr/share/ant
export MAKEFLAGS=-j4
mvn clean install
EOF
# make the script executable
chmod +x $runmaven
# run it
sudo $runmaven
# remove it or comment out to keep
rm $runmaven
is there any lvm.conf editor?
I'm trying to set global_filter, use_lvmtad and some other options, currently using sed:
sed -i /etc/lvm/lvm.conf \
-e "s/use_lvmetad = 1/use_lvmetad = 0/" \
-e "/^ *[^#] *global_filter/d" \
-e "/^devices {/a\ global_filter = [ \"r|/dev/drbd.*|\", \"r|/dev/dm-.*|\", \"r|/dev/zd.*|\" ]"
but I don't like this too much, is there any better way?
I found only lvmconfig tool, but it can only display certain configuration sections, and can't edit them.
If you using Ubuntu variant then you can use the LVM GUI to configure and manage the LVM. Refer this link
It seems that augtool is exactly what I was looking for.
These two packages should be enough to proper processing lvm.conf file:
apt install augeas-tools augeas-lenses
Example usage:
augtool print /files/etc/lvm/lvm.conf
And you should get the whole parse tree on stdout.
If the parser fails you won’t get any output, print the error message using:
augtool print /files/etc/lvm/lvm.conf/error
The augtool equivalent for the sed command from the original question:
augtool -s <<EOT
set /files/etc/lvm/lvm.conf/global/dict/use_lvmetad/int "0"
rm /files/etc/lvm/lvm.conf/devices/dict/global_filter
set /files/etc/lvm/lvm.conf/devices/dict/global_filter/list/0/str "r|^/dev/drbd.*|"
set /files/etc/lvm/lvm.conf/devices/dict/global_filter/list/1/str "r|/dev/dm-.*|"
set /files/etc/lvm/lvm.conf/devices/dict/global_filter/list/2/str "r|/dev/zd.*|"
EOT
I am trying to spellcheck a LaTeX document (using Word), and use OpenDetex to convert it to plain text. The command line with default parameters:
$ detex foo.tex > foo.txt
Problem: some garbage, especially bibliography ids from \citep{} and \citet{} commands stay in the text.
How can I exclude these specific tags?
The -c option only excludes \cite, but not \citep and \citet.
I tried using the -e option like:
$ detex -e citep foo.tex > foo.txt
to no avail.
The documentation is a bit vague on that:
detex [-e environment-list] [-c] [-l] [-n] [-s] [-t] [-w] [file[.tex] ]
...
-e <env-list> list of LaTeX environments to ignore\n
...
Any ideas how to make it work?
\citep and \citet are not LaTeX environments, they are commands, and as such the -e flag of detex has no effect on it. The flag -e is only for environments.
The new version of detex 2.8.2 that you can obtain here.
as long as the commands (\citep and \citet) do not start at the first character in a line -- that is a bug and will be fixed.
I have been using textmate for many years and I just made the switch to macvim and one thing that I used all the time with textmate was the command git df which in my .gitconfig was just an alias for
[alias]
df = !git diff | mate
and what that did was give me a screen like this
Is there a replacement in mvim that I can add somewhere for me to get similar behavior
I describe what I use here.
Basically, add the following lines to your "~/.gitconfig":
[diff]
tool = default-difftool
[difftool "default-difftool"]
cmd = default-difftool.sh $LOCAL $REMOTE
With the following wrapper script:
#! /bin/bash
if [[ -f /Applications/MacVim.app/Contents/MacOS/Vim ]]
then
# bypass mvim for speed
VIMPATH='/Applications/MacVim.app/Contents/MacOS/Vim -g -dO -f'
elif [[ -f /usr/local/bin/mvim ]]
then
# fall back to mvim
VIMPATH='mvim -d -f'
else
# fall back to original vim
VIMPATH='vimdiff'
fi
$VIMPATH $#
You can get the diff one file at a time by doing:
git difftool -t vimdiff
vimdiff can be replaced with gvimdiff for gvim, so I would assume you can also replace it with mvimdiff for macvim.
I am not sure of a way to pipe the entirety of git diff into vim though.
In this makefile
dirs = $(shell ls)
clean:
$(foreach dir,$(dirs),echo $(dir);)
The output is
$ make clean
echo bin; echo install.sh; echo Makefile; echo README.md; echo utils;
bin
install.sh
Makefile
README.md
utils
Why does it first show the command, then execute it?
How I can omit the first line?
Prepend the command with the # character. Example:
dirs = $(shell ls)
clean:
#$(foreach dir,$(dirs),echo $(dir);)
From the manual (5.2 Recipe Echoing, bold emphasis mine):
Normally make prints each line of the recipe before it is executed. We call this echoing because it gives the appearance that you are typing the lines yourself.
When a line starts with #, the echoing of that line is suppressed. The # is discarded before the line is passed to the shell. [...]
Alternatively:
The -s or --silent flag to make prevents all echoing, as if all recipes started with #.