In Makefiles, the order of execution is determined by the dependencies between targets. A target will only be executed if its dependencies have been updated or if the target does not exist.
However, in some cases, the execution of a command, such as mkdir, might not finish in time, causing subsequent commands to be executed before the directory is created. To avoid this issue, you can use the .PHONY special target in your Makefile. This will ensure that the command is executed every time the target is executed, regardless of whether the directory already exists.
Here's an example of how to use the .PHONY special target to ensure that the mkdir command is executed every time:
makefile
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.PHONY: directory
directory:
mkdir -p my_directory
# commands that depend on the directory
In this example, the .PHONY target directory is created, and the mkdir command is executed every time the directory target is executed, regardless of whether the my_directory directory already exists. This ensures that the mkdir command is executed in a timely manner and that the subsequent commands that depend on the directory are executed correctly.
Another solution is to use the && operator in your Makefile to ensure that the commands are executed in sequence. The && operator runs the subsequent command only if the previous command was successful. In the case of mkdir, you can use the && operator to run subsequent commands only after the directory has been successfully created.
Here's an example of how to use the && operator in a Makefile:
bash
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directory:
mkdir -p my_directory && \
# commands that depend on the directory
In this example, the mkdir command is executed first, followed by the subsequent commands that depend on the directory. The && operator ensures that the subsequent commands are executed only after the mkdir command has successfully created the directory.
Finally, you can also use the - operator in front of the mkdir command to ignore errors and continue execution even if the directory already exists.
Here's an example of how to use the - operator in a Makefile:
bash
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directory:
-mkdir -p my_directory
# commands that depend on the directory
In this example, the - operator in front of the mkdir command ensures that the subsequent commands are executed even if the mkdir command fails to create the directory because it already exists.
These are some ways to ensure that the mkdir command in your Makefile is executed in a timely manner and that subsequent commands are executed correctly.