add some settings for unifying develop environment

.clang-format

@@ -0,0 +1,35 @@
+---
+BasedOnStyle: Google
+LineEnding: LF
+ColumnLimit: 120
+# indent
+UseTab: Never
+IndentWidth: 4
+TabWidth: 4
+
+---
+## C/C++ style definitions
+Language: Cpp
+
+# include
+IncludeCategories:
+  - Regex: '../'
+
+# indent style
+IndentPPDirectives: AfterHash
+
+
+# Brace Position
+BreakBeforeBraces: Custom
+BraceWrapping:
+  AfterFunction: true
+  AfterStruct: true
+  AfterControlStatement: Never
+
+# Align style
+AlignConsecutiveDeclarations: true
+AlignTrailingComments: true
+AlignArrayOfStructures: Left
+AlignConsecutiveMacros: true
+AlignOperands: false
+

.editorconfig

@@ -0,0 +1,72 @@
+## EditorConfig is awesome: https://EditorConfig.org
+#
+# @(#)  editorconfig settings for c programming
+#
+# @version  1.0.0
+# @date		2024-03-07
+# @license  GPLv2
+#
+# @description <<
+# user default editorconfig :
+# for c programming with GitHub
+#
+#<<
+
+
+
+# top-most EditorConfig file
+root = true
+
+# Unix-style newlines with a newline ending every file
+[*]
+end_of_line = lf
+insert_final_newline = true
+
+# default character-set
+charset = utf-8
+
+# indent style
+indent_size = tab
+indent_style = tab
+tab_width=4
+
+# ext type settings
+
+# script executable
+[**.]
+indent_style = space
+indent_size = 2
+tab_width = 2
+
+### Programming language
+[**.{c,h}]
+indent_style = tab
+indent_size = tab
+tab_width = 4
+
+# shell script
+[**.{sh,bash}]
+indent_style = space
+indent_size = 2
+tab_width = 2
+
+### setting files
+
+# for git config
+[**.git*]
+indent_style = tab
+indent_size = tab
+tab_width = 4
+
+[**/git/*]
+indent_style = tab
+indent_size = tab
+tab_width = 4
+
+### document, etc
+# markdown
+[**.md]
+indent_size = tab
+tab_width = 2
+indent_style = space
+

.gitignore

@@ -1,3 +1,6 @@
+# @(#) : git ignore file for c codes
+#
+
 Makefile
 Makefile.in
 aclocal.m4
@@ -21,3 +24,40 @@ src/rlwrap
 stamp-h1
 tools/
 filters/RlwrapFilter.3pm
+**testit.trs
+
+### Generated by gibo (https://github.com/simonwhitaker/gibo)
+### https://raw.github.com/github/gitignore/4488915eec0b3a45b5c63ead28f286819c0917de/C++.gitignore
+
+# Prerequisites
+*.d
+
+# Compiled Object files
+*.slo
+*.lo
+*.o
+*.obj
+
+# Precompiled Headers
+*.gch
+*.pch
+
+# Compiled Dynamic libraries
+*.so
+*.dylib
+*.dll
+
+# Fortran module files
+*.mod
+*.smod
+
+# Compiled Static libraries
+*.lai
+*.la
+*.a
+*.lib
+
+# Executables
+*.exe
+*.out
+*.app