In this article, php editor Baicao will introduce you to two commonly used commands in Makefile: `go version` and `read`. When writing Makefile, these two commands can help us obtain and display the version information of the Go language, as well as obtain data from user input. By understanding and flexibly using these two commands, we can manage and build our Go projects more efficiently. Let’s learn more about it together!
Question content
I want to extract and verify the go version in the Makefile.
This works in the shell:
% go version | read _ _ version _ && echo "A $version Z" A go1.21.1 Z
But it doesn’t work in Makefile
check-golang-version: go version | read _ _ version _ && echo "A $$version Z"
result:
% make check-golang-version go version | read _ _ version _ && echo "A $version Z" A Z
Ultimately I want a check like this:
check-golang-version: go version | read _ _ version _ && test "$$version" = "go1.21.1" || $(error "wrong go version: $$version")
Solution
By default, make
uses /bin/sh
as the shell (see 5.3.2 Selecting a Shell).
And most likely when you execute the command in a shell, the shell is zsh
. zsh
Pipe behavior is different from most other shells. See https://riptutorial.com/zsh/example/19869/pipes-and -subshells for an example.
I recommend using go env GOVERSION
to get the version of go and assign it to a Makefile variable:
version = $(shell go env GOVERSION) check-golang-version: ifneq ($(version), go1.21.1) $(error wrong go version: $(version)) endif
The above is the detailed content of Makefile `go version` and `read` commands. For more information, please follow other related articles on the PHP Chinese website!

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