localPackages.biu: add env

local/pkgs/biu/.clangd

@@ -1,3 +1,3 @@
 CompileFlags:
   Add: [ -Wall, -Wextra, -std=c++23 ]
-  Compiler: gcc
+  Compiler: g++

local/pkgs/biu/CMakeLists.txt

@@ -22,7 +22,7 @@ find_path(NAMEOF_INCLUDE_DIR nameof.hpp REQUIRED)
 # find_library(BACKTRACE_LIB backtrace REQUIRED)
 
 # add_library(biu SHARED src/common.cpp src/logger.cpp src/string.cpp)
-add_library(biu SHARED src/common.cpp)
+add_library(biu SHARED src/common.cpp src/env.cpp)
 target_include_directories(biu PUBLIC
   $<BUILD_INTERFACE:${CMAKE_CURRENT_SOURCE_DIR}/include>
   $<INSTALL_INTERFACE:${CMAKE_INSTALL_INCLUDEDIR}>

local/pkgs/biu/README.md

@@ -40,3 +40,10 @@ std::regex operator""_re(const char* str, std::size_t len);
 inline namespace stream_operators { using namespace magic_enum::iostream_operators; }
 ```
 
+# `env`
+
+```c++
+bool is_interactive();
+std::optional<std::string> env(std::string name);
+std::map<std::string, std::string> env();
+```

local/pkgs/biu/include/biu.hpp

@@ -2,6 +2,7 @@
 // # include <biu/atomic/atomic.tpp>
 // # include <biu/called_by.hpp>
 # include <biu/common.tpp>
+# include <biu/env.hpp>
 // # include <biu/concepts.tpp>
 // # include <biu/format.tpp>
 // # include <biu/logger.tpp>

local/pkgs/biu/include/biu/env.hpp

@@ -0,0 +1,8 @@
+# pragma once
+# include <biu/common.hpp>
+
+namespace biu::env
+{
+  bool is_interactive();
+  std::optional<std::string> env(std::string name);
+}

local/pkgs/biu/src/common.cpp

@@ -5,8 +5,7 @@
 
 namespace biu
 {
-  std::regex literals::operator""_re(const char* str, std::size_t len)
-    { return std::regex{str, len}; }
+  std::regex literals::operator""_re(const char* str, std::size_t len) { return std::regex{str, len}; }
   namespace common
   {
     void block_forever() { std::promise<void>().get_future().wait(); std::unreachable(); }
@@ -25,12 +24,14 @@ namespace biu
       if (stdin)
       {
         process = std::make_unique<bp::child>
-          (program.string(), bp::args(args), bp::std_out > stdout, bp::std_err > stderr, bp::std_in < input, env);
+          (program.string(), bp::args(args), bp::std_out > stdout, bp::std_err > stderr,
+            bp::std_in < input, env);
         input << *stdin;
         input.pipe().close();
       }
       else process = std::make_unique<bp::child>
-        (program.string(), bp::args(args), bp::std_out > stdout, bp::std_err > stderr, bp::std_in < bp::null, env);
+        (program.string(), bp::args(args), bp::std_out > stdout, bp::std_err > stderr,
+          bp::std_in < bp::null, env);
       process->wait();
       return
       {

local/pkgs/biu/src/env.cpp

@@ -0,0 +1,12 @@
+# include <biu.hpp>
+# include <boost/process.hpp>
+
+namespace biu::env
+{
+  bool is_interactive() { return isatty(fileno(stdin)); }
+  std::optional<std::string> env(std::string name)
+  {
+    if (auto value = std::getenv(name.c_str()); !value) return std::nullopt;
+    else return value;
+  }
+}