I want to run a shell command within Emacs and capture the full output to a variable. Is there a way to do this? For example, I would like to be able to set hello-string to "hello" in the following manner:
(setq hello-string (capture-stdout-of-shell-command "/bin/echo hello"))
Does the function capture-stdout-of-shell-command exist, and if so what is its real name?
Does shell-command-to-string meet your purpose?
For example:
(shell-command-to-string "/bin/echo hello")
shell-command-to-string captures both stdout and stderr. Luckily we can just pipe the stderr to /dev/null: (shell-command-to-string "/bin/echo hello 2>/dev/null")I have a suggestion to made that extends Ise Wisteria's answer. Try using something like this:
(setq my_shell_output
(substring
(shell-command-to-string "/bin/echo hello")
0 -1))
This should set the string "hello" as the value of my_shell_output, but cleanly. Using (substring) eliminates the trailing \n that tends to occur when emacs calls out to a shell command. It bothers me in emacs running on Windows, and probably occurs on other platforms as well.
(defun my-shell-command-to-string (&rest cmd) (replace-regexp-in-string "\r?\n$" "" (shell-command-to-string (mapconcat 'identity cmd " "))))
\\' in there, not $.
echo hello is hello\n.
-n to stop outputting the trailing newline., e.g. echo -n helloFinally, the "git log" "--reverse" option came in handy ). Open a buffer with the current buffer file as of the most initial commit.
(vc-revision-other-window (car (process-lines "git" "log" "--format=%h" "--reverse")))
And on the question of
(setq hello-string (car (process-lines "echo" "hello")))
