If you’ve exported the environment variable: export demoPath=/usr/local/demo you can simply refer to it by name in the makefile (make imports all the environment variables you have set): DEMOPATH = ${demoPath} # Or $(demoPath) if you prefer. If you’ve not exported the environment variable, it is not accessible until you do export it, or unless … Read more
#!/bin/sh if [ “$#” -ne 1 ] || ! [ -d “$1” ]; then echo “Usage: $0 DIRECTORY” >&2 exit 1 fi Translation: If number of arguments is not (numerically) equal to 1 or the first argument is not a directory, output usage to stderr and exit with a failure status code. More friendly error … Read more
Make variables are not exported into the environment of processes make invokes… by default. However you can use make’s export to force them to do so. Change: test: NODE_ENV = test to this: test: export NODE_ENV = test (assuming you have a sufficiently modern version of GNU make >= 3.77 ).
Try this way: wc -l < file.txt
In general, that depends on your shell, but if you use bash, zsh, ksh or sh (as provided by dash), the following should work: if ! type “$foobar_command_name” > /dev/null; then # install foobar here fi For a real installation script, you’d probably want to be sure that type doesn’t return successfully in the case … Read more
An example to help you get off the ground. for f in *.jpg; do mv “$f” “$(echo “$f” | sed s/IMG/VACATION/)”; done In this example, I am assuming that all your image files contain the string IMG and you want to replace IMG with VACATION. The shell automatically evaluates *.jpg to all the matching files. … Read more
Use -F [field separator] to split the lines on “s: awk -F ‘”‘ ‘{print $2}’ your_input_file or for input from pipe <some_command> | awk -F ‘”‘ ‘{print $2}’ output: A B C D
Run cat then press keys to see the codes your shortcut send. (Press Ctrl+C to kill the cat when you’re done.) For me, (ubuntu, konsole, xterm) pressing Alt+← sends ^[[1;3D, so i would put in my .zshrc bindkey “^[[1;3C” forward-word bindkey “^[[1;3D” backward-word (Actually I prefer to use Ctrl + arrow to move word by … Read more
The command you are seeking is comm. eg:- comm -12 1.sorted.txt 2.sorted.txt Here: -1 : suppress column 1 (lines unique to 1.sorted.txt) -2 : suppress column 2 (lines unique to 2.sorted.txt)
You need to supply a filter as an argument. To pass the JSON through unmodified other than the pretty printing jq provides by default, use the identity filter .: curl -s https://api.github.com/users/octocat/repos | jq ‘.’ | cat