argv_from_stdin

README

Argv from Standard Input

Nearly the same as argv_from_environment but an attempt will be made to read configuration from stdin as well.

Standard Input

The address and file are read as whitespace-separated words from stdin, and override the environment variables. If only one word is read, it is taken to be the address.

EOF is necessary; if neither is to be read, redirect stdin from /dev/null.

Examples

Set the address and file via stdin:

echo localhost:5555 /etc/passwd | ./argv_from_stdin 

Set just the address via stdin:

echo localhost:5555 | ./argv_from_stdin 

Set neither via stdin:

./argv_from_stdin </dev/null

Environment Variables

The address and file may be set with environment variables, overriding compile-time settings, as follows

Default Variable	Description
ALPT4ATS_ADDRESS	TCP Server Address
ALPT4ATS_FILE	File to send on the TCP connection

The variable names may be changed at compile-time, as below.

Compile-time Config

Compile time configuration is possible with the linker's -X (as in go build -ldflags '-X main.Foo=bar'). The variables are as follows

Variable	Default	Description
main.Address	localhost:4444	TCP Server Address
main.AddressEnvVar	ALPT4ATS_ADDRESS	Environment variable which sets the TCP Server Address
main.File	/etc/hosts	File to send on the TCP connection
main.FileEnvVar	ALPT4ATS_FILE	Environment variable which sets the File to send on the TCP connection

When building with the Makefile these may be passed in with the LINKFLAGS environment variable, as in

LINKFLAGS="-X main.Address=example.com:8080" make

Documentation

Overview

Program argv_from_stdin - argv_from_environment which also tries to read config from stdin.