AcquireNet acquires a semaphore token for a network operation.

AddBuildFlagsNX adds the -n and -x build flags to the flag set.

AddChdirFlag adds the -C flag to the flag set.

AddModCommonFlags adds the module-related flags common to build commands and 'go mod' subcommands.

AddModFlag adds the -mod build flag to the flag set.

AppendPATH returns the result of appending PATH=$GOROOT/bin:$PATH (or the platform equivalent) to the environment base.

AppendPWD returns the result of appending PWD=dir to the environment base.

Cwd returns the current working directory at the time of the first call.

GOFLAGS returns the flags from $GOFLAGS.

InGOFLAGS returns whether GOFLAGS contains the given flag, such as "-mod".

InitGOFLAGS initializes the goflags list from $GOFLAGS.

IsNull reports whether the path is a common name for the null device.

IsTestFile reports whether the source file is a set of tests and should therefore be excluded from coverage analysis.

NetLimit returns the limit on concurrent network operations configured by GODEBUG=cmdgonetlimit, if any.

RelPaths returns a copy of paths with absolute paths made relative to the current directory if they would be shorter.

Run runs the command, with stdout and stderr connected to the go command's own stdout and stderr.

RunStdin is like run but connects Stdin.

SetFromGOFLAGS sets the flags in the given flag set using settings in $GOFLAGS.

ShortPath returns an absolute or relative name for path, whatever is shorter.

StartSigHandlers starts the signal handlers.

Tool returns the path to the named tool (for example, "vet").

Tool returns the path at which we expect to find the named tool (for example, "vet"), and the error (if any) from statting that path.

UncachedCwd returns the current working directory.

Interrupted is closed when the go command receives an interrupt signal.

Usage is the usage-reporting function, filled in by package main but here for reference by other packages.

A Command is an implementation of a go command like go build or go fix.

A StringsFlag is a command-line flag that interprets its argument as a space-separated list of possibly-quoted strings.