makefile - How does the make work when the file is not in target? -

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i looking code of libavcodec. makefile of https://github.com/libav/libav/tree/master/libavcodec#. instance, if execute make api-example.c, recognize it. while there no target api-example.c. moreover, when remove makefile directory, recognize target. i'm missing something.

make has number of built-in rules. if file asked make build exists, , there no target file defined gives prerequisite make can check see if it's date, file up-to-date definition: exists, , has no prerequisites.

the way target has no prerequisites can out of date if doesn't exist: has created.


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