第 12 章提示

12.1. 在 UTF-8 环境下构建
12.2. UTF-8 转换
12.3. Hints for Debugging

Please also read insightful pages linked from “Notes on Debian” by Russ Allbery (long time Debian developer) which have best practices for advanced packaging topics.

12.1. 在 UTF-8 环境下构建

构建环境的默认语言环境是 C。

某些程序（如 Python3 的 read 函数）会根据区域设置改变行为。

添加以下代码到 debian/rules 文件可以确保程序使用 C.UTF-8 的区域语言设置（locale）进行构建。

LC_ALL := C.UTF-8
export LC_ALL

12.2. UTF-8 转换

If upstream documents are encoded in old encoding schemes, converting them to UTF-8 is a good idea.

Use the iconv command in the libc-bin package to convert the encoding of plain text files.

[debhello] $ iconv -f latin1 -t utf8 foo_in.txt > foo_out.txt

使用 w3m(1) 将 HTML 文件转换为 UTF-8 纯文本文件。执行此操作时，请确保在 UTF-8 语言环境下执行它。

[debhello] $ LC_ALL=C.UTF-8 w3m -o display_charset=UTF-8 \
        -cols 70 -dump -no-graph -T text/html \
        < foo_in.html > foo_out.txt

在 debian/rules 文件的 override_dh_* 目标中运行这些脚本。

12.3. Hints for Debugging

当您遇到构建问题或者生成的二进制程序核心转储时，您需要自行解决他们。这就是除错（debug）。

This is too deep a topic to describe here. So, let me just list few pointers and hints for some typical debug tools.

Wikipedia: “core dump”
- “man core”
- Update the “/etc/security/limits.conf” file to include the following:
```
* soft core unlimited
```
- “ulimit -c unlimited” in ~/.bashrc
- “ulimit -a” to check
- Press Ctrl-\ or “kill -ABRT 'PID'” to make a core dump file
gdb - The GNU Debugger
- “info gdb”
- “Debugging with GDB” in /usr/share/doc/gdb-doc/html/gdb/index.html
strace - 跟踪系统调用和信号
- 使用 /usr/share/doc/strace/examples/ 中的 strace-graph 脚本来建立一个好看的树形图
- “man strace”
ltrace - 跟踪库调用
- “man ltrace”
“sh -n script.sh” - Syntax check of a Shell script
“sh -x script.sh” - Trace a Shell script
“python3 -m py_compile script.py” - Syntax check of a Python script
“python3 -mtrace --trace script.py” - Trace a Python script
“perl -I ../libpath -c script.pl” - Syntax check of a Perl script
“perl -d:Trace script.pl” - Trace a Perl script
- 安装 libterm-readline-gnu-perl 软件包或者同类型软件来添加输入行编辑功能与历史记录支持。
lsof - 按进程列出打开的文件
- “man lsof”

	提示
	script 命令能帮助记录控制台输出。

	提示
	在 ssh 命令中搭配使用 screen 和 tmux 命令，能够提供安全并且强健的远程连接终端。

	提示
	A Python- and Shell-like REPL (=READ + EVAL + PRINT + LOOP) environment for Perl is offered by the reply command from the libreply-perl (new) package and the re.pl command from the libdevel-repl-perl (old) package.

	提示
	The rlwrap and rlfe commands add input line editing capability with history support to any interactive commands. E.g. “rlwrap dash -i'” .