<!-- go.dev/issue/74667 -->
`cmd/doc`, and `go tool doc` have been deleted. `go doc` can be used as
a replacement for `go tool doc`: it takes the same flags and arguments and
has the same behavior.

*.pyc
._*
.nfs.*
[56789a].out
*~
*.orig
*.rej
*.exe
.*.swp
core
*.cgo*.go
*.cgo*.c
_cgo_*
_obj
_test
_testmain.go

/VERSION.cache
/bin/
/build.out
/doc/articles/wiki/*.bin
/goinstall.log
/last-change
/misc/cgo/life/run.out
/misc/cgo/stdio/run.out
/misc/cgo/testso/main
/pkg/
/src/*.*/
/src/cmd/cgo/zdefaultcc.go
/src/cmd/dist/dist
/src/cmd/go/internal/cfg/zdefaultcc.go

The stanza

	// #include <gmp.h>
	import "C"

is a signal to cgo.  The doc comment on the import of "C" provides
additional context for the C file.  Here it is just a single #include
but it could contain arbitrary C definitions to be imported and used.

Cgo recognizes any use of a qualified identifier C.xxx and uses gcc to
find the definition of xxx.  If xxx is a type, cgo replaces C.xxx with

## Tools {#tools}

### Go command {#go-command}

Android
=======

For details on developing Go for Android, see the documentation in the
mobile subrepository:

	https://github.com/golang/mobile

To run the standard library tests, enable Cgo and use an appropriate
C compiler from the Android NDK. For example,

	CGO_ENABLED=1 \
	GOOS=android \
	GOARCH=arm64 \
	CC_FOR_TARGET=$NDK/toolchains/llvm/prebuilt/linux-x86_64/bin/aarch64-linux-android21-clang \
	./all.bash

#!/bin/bash

set -e
# Enable tracing if set.
[ -n "$BASH_XTRACEFD" ] && set -x

function _init() {
	## All binaries are static make sure to disable CGO.
	export CGO_ENABLED=0

	## List of architectures and OS to test coss compilation.
	SUPPORTED_OSARCH="linux/ppc64le linux/mips64 linux/amd64 linux/arm64 linux/s390x darwin/arm64 darwin/amd64 freebsd/amd64 windows/amd64 linux/arm linux/386 netbsd/amd64 linux/mips openbsd/amd64 linux/riscv64"
}

SDK=iphonesimulator
PLATFORM=ios-simulator

if [ "$GOARCH" == "arm64" ]; then
	CLANGARCH="arm64"
else
	CLANGARCH="x86_64"
fi

SDK_PATH=`xcrun --sdk $SDK --show-sdk-path`

# cmd/cgo doesn't support llvm-gcc-4.2, so we have to use clang.
CLANG=`xcrun --sdk $SDK --find clang`

pkg syscall (linux-386), type SysProcAttr struct, PidFD *int #51246
pkg syscall (linux-386-cgo), type SysProcAttr struct, PidFD *int #51246
pkg syscall (linux-amd64), type SysProcAttr struct, PidFD *int #51246
pkg syscall (linux-amd64-cgo), type SysProcAttr struct, PidFD *int #51246
pkg syscall (linux-arm), type SysProcAttr struct, PidFD *int #51246
pkg syscall (linux-arm-cgo), type SysProcAttr struct, PidFD *int #51246

	}
	h.Uid = int(sys.Uid)
	h.Gid = int(sys.Gid)
	if doNameLookups {
		// Best effort at populating Uname and Gname.
		// The os/user functions may fail for any number of reasons
		// (not implemented on that platform, cgo not enabled, etc).
		if u, ok := userMap.Load(h.Uid); ok {
			h.Uname = u.(string)
		} else if u, err := user.LookupId(strconv.Itoa(h.Uid)); err == nil {
			h.Uname = u.Username
			userMap.Store(h.Uid, h.Uname)
		}