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Rephrase documentation for both makeWrapper implementations

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Doron Behar 2021-12-09 16:02:02 +02:00
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commit c42e6741b2
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22
doc/stdenv/stdenv.chapter.md
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@ -774,7 +774,7 @@ The standard environment provides a number of useful functions.
### `makeWrapper` \<executable\> \<wrapperfile\> \<args\> {#fun-makeWrapper}
Constructs a wrapper for a program with various possible arguments. It is defined as part of a setup-hook by the same name, so to use it you have to add `makeWrapper` to your `nativeBuildInputs`. Here's a usage example:
Constructs a wrapper for a program with various possible arguments. It is defined as part of 2 setup-hooks named `makeWrapper` and `makeBinaryWrapper` that implement the same bash functions. Hence, to use it you have to add `makeWrapper` to your `nativeBuildInputs`. Here's an example usage:
```bash
# adds `FOOBAR=baz` to `$out/bin/foo`’s environment
@ -786,17 +786,11 @@ makeWrapper $out/bin/foo $wrapperfile --set FOOBAR baz
makeWrapper $out/bin/foo $wrapperfile --prefix PATH : ${lib.makeBinPath [ hello git ]}
```
There’s many more kinds of arguments, they are documented in `nixpkgs/pkgs/build-support/setup-hooks/make-wrapper.sh`.
There’s many more kinds of arguments, they are documented in `nixpkgs/pkgs/build-support/setup-hooks/make-wrapper.sh` for the `makeWrapper` implementation and in `nixpkgs/pkgs/build-support/setup-hooks/make-binary-wrapper.sh` for the `makeBinaryWrapper` implementation.
`wrapProgram` is a convenience function you probably want to use most of the time.
`wrapProgram` is a convenience function you probably want to use most of the time, implemented by both `makeWrapper` and `makeBinaryWrapper`.
### `makeBinaryWrapper` \<executable\> \<wrapperfile\> \<args\> {#fun-makeBinaryWrapper}
A setup-hook very similar to `makeWrapper`, only it creates a tiny _compiled_ wrapper executable, that can be used as a shebang interpreter. This is needed mostly on Darwin, where shebangs cannot point to scripts, [due to a limitation with the `execve`-syscall](https://stackoverflow.com/questions/67100831/macos-shebang-with-absolute-path-not-working). The arguments it accepts are similar to those of `makeWrapper` and they are documented in `nixpkgs/pkgs/build-support/setup-hooks/make-binary-wrapper.sh`.
Compiled wrappers generated by `makeBinaryWrapper` can be inspected with `less <path-to-wrapper>` - by scrolling past the binary data you should be able to see the C code that generated the executable and there see the environment variables that were injected into the wrapper.
Similarly to `wrapProgram`, the `makeBinaryWrapper` setup-hook provides a `binaryWrapProgram` with similar command line arguments.
Using the `makeBinaryWrapper` implementation is usually preferred, as it creates a tiny _compiled_ wrapper executable, that can be used as a shebang interpreter. This is needed mostly on Darwin, where shebangs cannot point to scripts, [due to a limitation with the `execve`-syscall](https://stackoverflow.com/questions/67100831/macos-shebang-with-absolute-path-not-working). Compiled wrappers generated by `makeBinaryWrapper` can be inspected with `less <path-to-wrapper>` - by scrolling past the binary data you should be able to see the shell command that generated the executable and there see the environment variables that were injected into the wrapper.
### `substitute` \<infile\> \<outfile\> \<subs\> {#fun-substitute}
@ -871,13 +865,7 @@ someVar=$(stripHash $name)
### `wrapProgram` \<executable\> \<makeWrapperArgs\> {#fun-wrapProgram}
Convenience function for `makeWrapper` that replaces `<\executable\>` with a wrapper that executes the original program. It takes all the same arguments as `makeWrapper`, except for `--argv0`.
If you will apply it multiple times, it will overwrite the wrapper file and you will end up with double wrapping, which should be avoided.
### `binaryWrapProgram` \<executable\> \<makeBinaryWrapperArgs\> {#fun-binaryWrapProgram}
Convenience function for `makeBinaryWrapper` that replaces `<\executable\>` with a wrapper that executes the original program. It takes all the same arguments as `makeBinaryWrapper`, except for `--argv0`.
Convenience function for `makeWrapper` that replaces `<\executable\>` with a wrapper that executes the original program. It takes all the same arguments as `makeWrapper`, except for `--inherit-argv0` (used by the `makeBinaryWrapper` implementation and `--argv0` (used by both `makeWrapper` and `makeBinaryWrapper` wrapper implementations).
If you will apply it multiple times, it will overwrite the wrapper file and you will end up with double wrapping, which should be avoided.