Ninja normally deletes each response .rsp file as soon as the compilation is successful. When debugging a program, we may need to see all the commands run before failure, so keeping the .rsp files is useful.

Ninja will keep the .rsp files after compilation by using option:

ninja -d keeprsp

Notes

Ninja is the build backend used by Meson build system as a fast, modern replacement for GNU Make. On Windows, most build systems use .rsp response files. .rsp files are simply a plain text file containing the command fragment to be run on the command line. For example, on Linux we might do:

cc -Ifoo hello.c -lm

On Windows, the build system including Meson and Ninja will do like:

cc foo.rsp

where file foo.rsp contains

-Ifoo hello.c -lm