目录
這裏我給出一些 Debian 系統中的信息,幫助學習編程的人找出打包的源代碼。下面是值得關注的軟件包和與之對應的文檔。
表 12.1. 幫助編程的軟件包清單
軟件包 | 流行度 | 大小 | 包 |
---|---|---|---|
autoconf
|
V:25, I:221 | 1868 |
由 autoconf-doc 包提供的“info autoconf ”
|
automake
|
V:23, I:213 | 1707 |
由 automake1.10-doc 包提供的“info automake ”
|
bash
|
V:859, I:999 | 5786 |
由 bash-doc 包提供的“info bash ”
|
bison
|
V:11, I:114 | 2051 |
由 bison-doc 包提供的“info bison ”
|
cpp
|
V:407, I:815 | 41 |
由 cpp-doc 包提供的“info cpp ”
|
ddd
|
V:1, I:13 | 3692 |
由 ddd-doc 包提供的“info ddd ”
|
exuberant-ctags
|
V:7, I:37 | 333 | exuberant-ctags(1) |
flex
|
V:10, I:101 | 1077 |
由 flex-doc 包提供的“info flex ”
|
gawk
|
V:352, I:468 | 2029 |
由 gawk-doc 包提供的“info gawk ”
|
gcc
|
V:163, I:611 | 41 |
由 gcc-doc 包提供的“info gcc ”
|
gdb
|
V:23, I:142 | 7307 |
由 gdb-doc 包提供的“info gdb ”
|
gettext
|
V:53, I:371 | 7035 |
由 gettext-doc 包提供的“info gettext ”
|
gfortran
|
V:22, I:62 | 16 |
由 gfortran-doc 包提供的“info
gfortran ”(Fortran 95)
|
fpc
|
I:4 | 113 | fpc(1)
和由 fp-docs 包提供的 html 文檔(Pascal)
|
glade
|
V:1, I:12 | 2212 | 通過 UI Builder 菜單提供的文檔 |
libc6
|
V:927, I:998 | 10670 |
通過 glibc-doc 和 glibc-doc-reference
提供的“info libc ”
|
make
|
V:164, I:626 | 1195 |
通過 make-doc 包提供的“info make ”
|
xutils-dev
|
V:2, I:19 | 1465 | imake(1),xmkmf(1) 等。 |
mawk
|
V:402, I:997 | 198 | mawk(1) |
perl
|
V:617, I:995 | 674 | perl(1)
以及通過 perl-doc 和 perl-doc-html 提供的 html
文檔
|
python
|
V:674, I:988 | 647 | python(1)
以及通過 python-doc 包提供的 html 文檔 |
tcl8.4
|
V:4, I:66 | 184 | tcl(3)
以及通過 tcl8.4-doc 包提供的更詳細的手冊頁文檔 |
tk8.4
|
V:2, I:42 | 185 | tk(3)
以及通過 tk8.4-doc 包提供的更詳細的手冊頁文檔 |
ruby
|
V:87, I:316 | 37 | ruby(1)
以及通過 ri 包提供的交互式參考手冊 |
vim
|
V:127, I:390 | 2366 |
通過 vim-doc 包提供的幫助(F1)菜單
|
susv2
|
I:0 | 15 | 通過“單一UNIX規範(版本2)”獲取(英語文檔) |
susv3
|
I:0 | 15 | 通過“單一UNIX規範(版本3)”獲取(英語文檔) |
安裝 manpages
和 manpages-dev
包之後,可以通過運行“man 名稱
”查看手冊頁中的參考信息。安裝了 GNU
工具的相關文檔包之後,可以通過運行“info 程序名稱
”查看參考文檔。某些 GFDL 協議的文檔與 DFSG
並不兼容,所以你可能需要在 main
倉庫中包含 contrib
和
non-free
才能下載並安裝它們。
![]() |
警告 |
---|---|
不要用“ |
![]() |
小心 |
---|---|
你可以把從源代碼編譯得到的程序直接放到“ |
![]() |
提示 |
---|---|
“歌曲:99瓶啤酒”的代碼示例可以給你提供實踐各種語言的好範本。 |
Shell 腳本 是指包含有下面格式的可執行的文本文件。
#!/bin/sh …… 命令
第一行指明瞭讀取並執行這個文件的 shell 解釋器。
讀懂 shell 腳本的最好 辦法是先理解類 UNIX 系統是如何工作的。這裏有一些 shell 編程的提示。看看“Shell 錯誤”(http://www.greenend.org.uk/rjk/2001/04/shell.html),可以從錯誤中學習。
不像 shell 交互模式(參見第 1.5 节 “簡單 shell 命令” 和 第 1.6 节 “類 Unix 的文本處理”),shell 腳本會頻繁使用參數、條件和循環等。
系統中的許多腳本都可以通過任意 POSIX shell(參見 表 1.13 “List of shell programs”)來執行。系統的默認 shell
是“/bin/sh
”,它是某個實際 shell 程序的鏈接。
對 lenny
或更老的系統來說,它是
bash(1)
對 squeeze
或更新的系統來說,它是
dash(1)
Avoid writing a shell script with bashisms or zshisms to make it portable among all POSIX shells. You can check it using checkbashisms(1).
表 12.2. List of typical bashisms
Good: POSIX | Avoid: bashism |
---|---|
if [ "$foo" = "$bar" ] ; then …
|
if [ "$foo" == "$bar" ] ; then …
|
diff -u file.c.orig file.c
|
diff -u file.c{.orig,}
|
mkdir /foobar /foobaz
|
mkdir /foo{bar,baz}
|
funcname() { … }
|
function funcname() { … }
|
octal format: "\377 "
|
hexadecimal format: "\xff "
|
The "echo
" command must be used with following cares
since its implementation differs among shell builtin and external commands.
Avoid using any command options except "-n
".
Avoid using escape sequences in the string since their handling varies.
![]() |
注意 |
---|---|
Although " |
![]() |
提示 |
---|---|
Use the " |
Special shell parameters are frequently used in the shell script.
表 12.3. List of shell parameters
shell parameter | value |
---|---|
$0
|
name of the shell or shell script |
$1
|
first (1st) shell argument |
$9
|
ninth (9th) shell argument |
$#
|
number of positional parameters |
"$*"
|
"$1 $2 $3 $4 … "
|
"$@"
|
"$1" "$2" "$3" "$4" …
|
$?
|
exit status of the most recent command |
$$
|
PID of this shell script |
$!
|
PID of most recently started background job |
Basic parameter expansions to remember are as follows.
表 12.4. List of shell parameter expansions
parameter expression form |
value if var is set
|
value if var is not set
|
---|---|---|
${var:-string}
|
"$var "
|
"string "
|
${var:+string}
|
"string "
|
"null "
|
${var:=string}
|
"$var "
|
"string " (and run "var=string ")
|
${var:?string}
|
"$var "
|
echo "string " to stderr (and exit with error)
|
Here, the colon ":
" in all of these operators is actually
optional.
with ":
" = operator
test for exist and not null
without ":
" = operator
test for exist only
表 12.5. List of key shell parameter substitutions
parameter substitution form | result |
---|---|
${var%suffix}
|
remove smallest suffix pattern |
${var%%suffix}
|
remove largest suffix pattern |
${var#prefix}
|
remove smallest prefix pattern |
${var##prefix}
|
remove largest prefix pattern |
Each command returns an exit status which can be used for conditional expressions.
Success: 0 ("True")
Error: non 0 ("False")
![]() |
注意 |
---|---|
"0" in the shell conditional context means "True", while "0" in the C conditional context means "False". |
![]() |
注意 |
---|---|
" |
Basic conditional idioms to remember are the following.
"<command> && <if_success_run_this_command_too>
|| true
"
"<command> || <if_not_success_run_this_command_too> ||
true
"
A multi-line script snippet as the following
if [ <conditional_expression> ]; then <if_success_run_this_command> else <if_not_success_run_this_command> fi
Here trailing "|| true
" was needed to ensure this shell
script does not exit at this line accidentally when shell is invoked with
"-e
" flag.
表 12.6. List of file comparison operators in the conditional expression
equation | condition to return logical true |
---|---|
-e <file>
|
<file> exists |
-d <file>
|
<file> exists and is a directory |
-f <file>
|
<file> exists and is a regular file |
-w <file>
|
<file> exists and is writable |
-x <file>
|
<file> exists and is executable |
<file1> -nt <file2>
|
<file1> is newer than <file2> (modification) |
<file1> -ot <file2>
|
<file1> is older than <file2> (modification) |
<file1> -ef <file2>
|
<file1> and <file2> are on the same device and the same inode number |
表 12.7. List of string comparison operators in the conditional expression
equation | condition to return logical true |
---|---|
-z <str>
|
the length of <str> is zero |
-n <str>
|
the length of <str> is non-zero |
<str1> = <str2>
|
<str1> and <str2> are equal |
<str1> != <str2>
|
<str1> and <str2> are not equal |
<str1> < <str2>
|
<str1> sorts before <str2> (locale dependent) |
<str1> > <str2>
|
<str1> sorts after <str2> (locale dependent) |
Arithmetic integer comparison operators
in the conditional expression are "-eq
",
"-ne
", "-lt
",
"-le
", "-gt
", and
"-ge
".
There are several loop idioms to use in POSIX shell.
"for x in foo1 foo2 … ; do command ; done
" loops by
assigning items from the list "foo1 foo2 …
" to variable
"x
" and executing "command
".
"while condition ; do command ; done
" repeats
"command
" while "condition
" is true.
"until condition ; do command ; done
" repeats
"command
" while "condition
" is not
true.
"break
" enables to exit from the loop.
"continue
" enables to resume the next iteration of the
loop.
![]() |
提示 |
---|---|
The C-language like numeric iteration can be
realized by using
seq(1)
as the " |
The shell processes a script roughly as the following sequence.
The shell reads a line.
The shell groups a part of the line as one
token if it is within "…"
or
'…'
.
The shell splits other part of a line into tokens by the following.
Whitespaces: <space> <tab> <newline>
Metacharacters: < > | ; & ( )
The shell checks the reserved word for
each token to adjust its behavior if not within "…"
or
'…'
.
reserved word: if then elif else
fi for in while unless do done case esac
The shell expands alias if not within
"…"
or '…'
.
The shell expands tilde if not within
"…"
or '…'
.
"~
" → current user's home directory
"~<user>
" → <user>
's home
directory
The shell expands parameter to its value
if not within '…'
.
parameter:
"$PARAMETER
" or "${PARAMETER}
"
The shell expands command substitution if
not within '…'
.
"$( command )
" → the output of
"command
"
"` command `
" → the output of
"command
"
The shell expands pathname glob to
matching file names if not within "…"
or
'…'
.
*
→ any characters
?
→ one character
[…]
→ any one of the characters in "…
"
The shell looks up command from the following and execute it.
function definition
builtin command
executable file in
"$PATH
"
The shell goes to the next line and repeats this process again from the top of this sequence.
Single quotes within double quotes have no effect.
Executing "set -x
" in the shell or invoking the shell
with "-x
" option make the shell to print all of commands
executed. This is quite handy for debugging.
In order to make your shell program as portable as possible across Debian systems, it is a good idea to limit utility programs to ones provided by essential packages.
"aptitude search ~E
" lists essential packages.
"dpkg -L <package_name> |grep '/man/man.*/'
" lists
manpages for commands offered by <package_name>
package.
表 12.8. List of packages containing small utility programs for shell scripts
軟件包 | 流行度 | 大小 | 說明 |
---|---|---|---|
coreutils
|
V:876, I:999 | 14783 | GNU core utilities |
debianutils
|
V:930, I:999 | 213 | miscellaneous utilities specific to Debian |
bsdmainutils
|
V:861, I:998 | 558 | collection of more utilities from FreeBSD |
bsdutils
|
V:843, I:999 | 230 | basic utilities from 4.4BSD-Lite |
moreutils
|
V:4, I:18 | 184 | additional Unix utilities |
![]() |
提示 |
---|---|
Although |
The user interface of a simple shell program can be improved from dull
interaction by echo
and read
commands
to more interactive one by using one of the so-called dialog program etc.
表 12.9. List of user interface programs
軟件包 | 流行度 | 大小 | 說明 |
---|---|---|---|
x11-utils
|
V:305, I:637 | 603 | xmessage(1): display a message or query in a window (X) |
whiptail
|
V:431, I:996 | 68 | displays user-friendly dialog boxes from shell scripts (newt) |
dialog
|
V:25, I:145 | 1099 | displays user-friendly dialog boxes from shell scripts (ncurses) |
zenity
|
V:108, I:432 | 349 | display graphical dialog boxes from shell scripts (gtk2.0) |
ssft
|
V:0, I:0 | 129 | Shell Scripts Frontend Tool (wrapper for zenity, kdialog, and dialog with gettext) |
gettext
|
V:53, I:371 | 7035 |
"/usr/bin/gettext.sh ": translate message
|
Here is a simple script which creates ISO image with RS02 data supplemented by dvdisaster(1).
#!/bin/sh -e # gmkrs02 : Copyright (C) 2007 Osamu Aoki <osamu@debian.org>, Public Domain #set -x error_exit() { echo "$1" >&2 exit 1 } # Initialize variables DATA_ISO="$HOME/Desktop/iso-$$.img" LABEL=$(date +%Y%m%d-%H%M%S-%Z) if [ $# != 0 ] && [ -d "$1" ]; then DATA_SRC="$1" else # Select directory for creating ISO image from folder on desktop DATA_SRC=$(zenity --file-selection --directory \ --title="Select the directory tree root to create ISO image") \ || error_exit "Exit on directory selection" fi # Check size of archive xterm -T "Check size $DATA_SRC" -e du -s $DATA_SRC/* SIZE=$(($(du -s $DATA_SRC | awk '{print $1}')/1024)) if [ $SIZE -le 520 ] ; then zenity --info --title="Dvdisaster RS02" --width 640 --height 400 \ --text="The data size is good for CD backup:\\n $SIZE MB" elif [ $SIZE -le 3500 ]; then zenity --info --title="Dvdisaster RS02" --width 640 --height 400 \ --text="The data size is good for DVD backup :\\n $SIZE MB" else zenity --info --title="Dvdisaster RS02" --width 640 --height 400 \ --text="The data size is too big to backup : $SIZE MB" error_exit "The data size is too big to backup :\\n $SIZE MB" fi # only xterm is sure to have working -e option # Create raw ISO image rm -f "$DATA_ISO" || true xterm -T "genisoimage $DATA_ISO" \ -e genisoimage -r -J -V "$LABEL" -o "$DATA_ISO" "$DATA_SRC" # Create RS02 supplemental redundancy xterm -T "dvdisaster $DATA_ISO" -e dvdisaster -i "$DATA_ISO" -mRS02 -c zenity --info --title="Dvdisaster RS02" --width 640 --height 400 \ --text="ISO/RS02 data ($SIZE MB) \\n created at: $DATA_ISO" # EOF
You may wish to create launcher on the desktop with command set something
like "/usr/local/bin/gmkrs02 %d
".
Make is a utility to maintain groups of
programs. Upon execution of
make(1),
make
read the rule file, "Makefile
",
and updates a target if it depends on prerequisite files that have been
modified since the target was last modified, or if the target does not
exist. The execution of these updates may occur concurrently.
The rule file syntax is the following.
target: [ prerequisites ... ] [TAB] command1 [TAB] -command2 # ignore errors [TAB] @command3 # suppress echoing
Here "[TAB]
" is a TAB code. Each line is interpreted by
the shell after make variable substitution. Use "\
" at
the end of a line to continue the script. Use "$$
" to
enter "$
" for environment values for a shell script.
Implicit rules for the target and prerequisites can be written, for example, by the following.
%.o: %.c header.h
Here, the target contains the character "%
" (exactly one
of them). The "%
" can match any nonempty substring in the
actual target filenames. The prerequisites likewise use
"%
" to show how their names relate to the actual target
name.
表 12.10. List of make automatic variables
automatic variable | value |
---|---|
$@
|
target |
$<
|
first prerequisite |
$?
|
all newer prerequisites |
$^
|
all prerequisites |
$*
|
"% " matched stem in the target pattern
|
表 12.11. List of make variable expansions
variable expansion | 說明 |
---|---|
foo1 := bar
|
one-time expansion |
foo2 = bar
|
recursive expansion |
foo3 += bar
|
append |
Run "make -p -f/dev/null
" to see automatic internal
rules.
You can set up proper environment to compile programs written in the C programming language by the following.
# apt-get install glibc-doc manpages-dev libc6-dev gcc build-essential
The libc6-dev
package, i.e., GNU C Library, provides
C standard library which is
collection of header files and library routines used by the C programming
language.
See references for C as the following.
"info libc
" (C library function reference)
gcc(1)
and "info gcc
"
each_C_library_function_name(3)
Kernighan & Ritchie, "The C Programming Language", 2nd edition (Prentice Hall)
A simple example "example.c
" can compiled with a library
"libm
" into an executable
"run_example
" by the following.
$ cat > example.c << EOF #include <stdio.h> #include <math.h> #include <string.h> int main(int argc, char **argv, char **envp){ double x; char y[11]; x=sqrt(argc+7.5); strncpy(y, argv[0], 10); /* prevent buffer overflow */ y[10] = '\0'; /* fill to make sure string ends with '\0' */ printf("%5i, %5.3f, %10s, %10s\n", argc, x, y, argv[1]); return 0; } EOF $ gcc -Wall -g -o run_example example.c -lm $ ./run_example 1, 2.915, ./run_exam, (null) $ ./run_example 1234567890qwerty 2, 3.082, ./run_exam, 1234567890qwerty
Here, "-lm
" is needed to link library
"/usr/lib/libm.so
" from the libc6
package for
sqrt(3).
The actual library is in "/lib/
" with filename
"libm.so.6
", which is a symlink to
"libm-2.7.so
".
Look at the last parameter in the output text. There are more than 10
characters even though "%10s
" is specified.
The use of pointer memory operation functions without boundary checks, such as sprintf(3) and strcpy(3), is deprecated to prevent buffer overflow exploits that leverage the above overrun effects. Instead, use snprintf(3) and strncpy(3).
Debug is important part of programing activities. Knowing how to debug programs makes you a good Debian user who can produce meaningful bug reports.
Primary debugger on Debian is gdb(1) which enables you to inspect a program while it executes.
Let's install gdb
and related programs by the following.
# apt-get install gdb gdb-doc build-essential devscripts
Good tutorial of gdb
is provided by "info
gdb
" or found elsewhere on the
web. Here is a simple example of using
gdb(1)
on a "program
" compiled with the "-g
"
option to produce debugging information.
$ gdb program (gdb) b 1 # set break point at line 1 (gdb) run args # run program with args (gdb) next # next line ... (gdb) step # step forward ... (gdb) p parm # print parm ... (gdb) p parm=12 # set value to 12 ... (gdb) quit
![]() |
提示 |
---|---|
Many gdb(1) commands can be abbreviated. Tab expansion works as in the shell. |
Since all installed binaries should be stripped on the Debian system by
default, most debugging symbols are removed in the normal package. In order
to debug Debian packages with
gdb(1),
corresponding *-dbg
packages need to be installed
(e.g. libc6-dbg
in the case of libc6
).
If a package to be debugged does not provide its *-dbg
package, you need to install it after rebuilding it by the following.
$ mkdir /path/new ; cd /path/new $ sudo apt-get update $ sudo apt-get dist-upgrade $ sudo apt-get install fakeroot devscripts build-essential $ sudo apt-get build-dep source_package_name $ apt-get source package_name $ cd package_name*
Fix bugs if needed.
Bump package version to one which does not collide with official Debian
versions, e.g. one appended with "+debug1
" when
recompiling existing package version, or one appended with
"~pre1
" when compiling unreleased package version by the
following.
$ dch -i
Compile and install packages with debug symbols by the following.
$ export DEB_BUILD_OPTIONS=nostrip,noopt $ debuild $ cd .. $ sudo debi package_name*.changes
You need to check build scripts of the package and ensure to use
"CFLAGS=-g -Wall
" for compiling binaries.
When you encounter program crash, reporting bug report with cut-and-pasted backtrace information is a good idea.
The backtrace can be obtained by the following steps.
Run the program under gdb(1).
Reproduce crash.
It causes you to be dropped back to the gdb
prompt.
Type "bt
" at the gdb
prompt.
In case of program freeze, you can crash the program by pressing
Ctrl-C
in the terminal running gdb
to
obtain gdb
prompt.
![]() |
提示 |
---|---|
Often, you see a backtrace where one or more of the top lines are in
" |
$ MALLOC_CHECK_=2 gdb hello
表 12.12. List of advanced gdb commands
命令 | description for command objectives |
---|---|
(gdb) thread apply all bt
|
get a backtrace for all threads for multi-threaded program |
(gdb) bt full
|
get parameters came on the stack of function calls |
(gdb) thread apply all bt full
|
get a backtrace and parameters as the combination of the preceding options |
(gdb) thread apply all bt full 10
|
get a backtrace and parameters for top 10 calls to cut off irrelevant output |
(gdb) set logging on
|
write log of gdb output to a file (the default is
"gdb.txt ")
|
If a GNOME program preview1
has received an X error, you
should see a message as follows.
The program 'preview1' received an X Window System error.
If this is the case, you can try running the program with
"--sync
", and break on the
"gdk_x_error
" function in order to obtain a backtrace.
Use ldd(1) to find out a program's dependency on libraries by the followings.
$ ldd /bin/ls librt.so.1 => /lib/librt.so.1 (0x4001e000) libc.so.6 => /lib/libc.so.6 (0x40030000) libpthread.so.0 => /lib/libpthread.so.0 (0x40153000) /lib/ld-linux.so.2 => /lib/ld-linux.so.2 (0x40000000)
For ls(1) to work in a `chroot`ed environment, the above libraries must be available in your `chroot`ed environment.
There are several memory leak detection tools available in Debian.
表 12.13. List of memory leak detection tools
軟件包 | 流行度 | 大小 | 說明 |
---|---|---|---|
libc6-dev
|
V:266, I:619 | 15620 | mtrace(1): malloc debugging functionality in glibc |
valgrind
|
V:8, I:57 | 64044 | memory debugger and profiler |
kmtrace
|
V:1, I:19 | 310 | KDE memory leak tracer using glibc's mtrace(1) |
alleyoop
|
V:0, I:1 | 948 | GNOME front-end to the Valgrind memory checker |
electric-fence
|
V:0, I:6 | 49 | malloc(3) debugger |
leaktracer
|
V:0, I:3 | 56 | memory-leak tracer for C++ programs |
libdmalloc5
|
V:0, I:3 | 307 | debug memory allocation library |
There are lint like tools for static code analysis.
表 12.14. List of tools for static code analysis
軟件包 | 流行度 | 大小 | 說明 |
---|---|---|---|
splint
|
V:0, I:5 | 1801 | tool for statically checking C programs for bugs |
flawfinder
|
V:0, I:0 | 175 | tool to examine C/C++ source code and looks for security weaknesses |
perl
|
V:617, I:995 | 674 | interpreter with internal static code checker: B::Lint(3perl) |
pylint
|
V:5, I:15 | 876 | Python code static checker |
weblint-perl
|
V:0, I:2 | 34 | syntax and minimal style checker for HTML |
linklint
|
V:0, I:1 | 343 | fast link checker and web site maintenance tool |
libxml2-utils
|
V:23, I:324 | 176 | utilities with xmllint(1) to validate XML files |
Flex is a Lex-compatible fast lexical analyzer generator.
Tutorial for
flex(1)
can be found in "info flex
".
You need to provide your own "main()
" and
"yywrap()
". Otherwise, your flex program should look
like this to compile without a library. This is because that
"yywrap
" is a macro and "%option main
"
turns on "%option noyywrap
" implicitly.
%option main %% .|\n ECHO ; %%
Alternatively, you may compile with the "-lfl
" linker
option at the end of your
cc(1)
command line (like AT&T-Lex with "-ll
"). No
"%option
" is needed in this case.
Several packages provide a Yacc-compatible lookahead LR parser or LALR parser generator in Debian.
表 12.15. List of Yacc-compatible LALR parser generators
軟件包 | 流行度 | 大小 | 說明 |
---|---|---|---|
bison
|
V:11, I:114 | 2051 | GNU LALR parser generator |
byacc
|
V:0, I:7 | 166 | Berkeley LALR parser generator |
btyacc
|
V:0, I:0 | 248 |
backtracking parser generator based on byacc
|
Tutorial for
bison(1)
can be found in "info bison
".
You need to provide your own "main()
" and
"yyerror()
". "main()
" calls
"yyparse()
" which calls "yylex()
",
usually created with Flex.
%% %%
Autoconf is a tool for producing shell scripts that automatically configure software source code packages to adapt to many kinds of Unix-like systems using the entire GNU build system.
autoconf(1)
produces the configuration script
"configure
". "configure
" automatically
creates a customized "Makefile
" using the
"Makefile.in
" template.
![]() |
警告 |
---|---|
Do not overwrite system files with your compiled programs when installing them. |
Debian does not touch files in "/usr/local/
" or
"/opt
". So if you compile a program from source, install
it into "/usr/local/
" so it does not interfere with
Debian.
$ cd src $ ./configure --prefix=/usr/local $ make $ make install # this puts the files in the system
If you have the original source and if it uses autoconf(1)/automake(1) and if you can remember how you configured it, execute as follows to uninstall the program.
$ ./configure "all-of-the-options-you-gave-it" # make uninstall
Alternatively, if you are absolutely sure that the install process puts
files only under "/usr/local/
" and there is nothing
important there, you can erase all its contents by the following.
# find /usr/local -type f -print0 | xargs -0 rm -f
If you are not sure where files are installed, you should consider using
checkinstall(8)
from the checkinstall
package, which provides a clean
path for the uninstall. It now supports to create a Debian package with
"-D
" option.
Although any AWK scripts can be automatically rewritten in Perl using a2p(1), one-liner AWK scripts are best converted to one-liner Perl scripts manually.
Let's think following AWK script snippet.
awk '($2=="1957") { print $3 }' |
This is equivalent to any one of the following lines.
perl -ne '@f=split; if ($f[1] eq "1957") { print "$f[2]\n"}' |
perl -ne 'if ((@f=split)[1] eq "1957") { print "$f[2]\n"}' |
perl -ne '@f=split; print $f[2] if ( $f[1]==1957 )' |
perl -lane 'print $F[2] if $F[1] eq "1957"' |
perl -lane 'print$F[2]if$F[1]eq+1957' |
The last one is a riddle. It took advantage of following Perl features.
The whitespace is optional.
The automatic conversion exists from number to the string.
See perlrun(1) for the command-line options. For more crazy Perl scripts, Perl Golf may be interesting.
Basic interactive dynamic web pages can be made as follows.
Queries are presented to the browser user using HTML forms.
Filling and clicking on the form entries sends one of the following URL string with encoded parameters from the browser to the web server.
"http://www.foo.dom/cgi-bin/program.pl?VAR1=VAL1&VAR2=VAL2&VAR3=VAL3
"
"http://www.foo.dom/cgi-bin/program.py?VAR1=VAL1&VAR2=VAL2&VAR3=VAL3
"
"http://www.foo.dom/program.php?VAR1=VAL1&VAR2=VAL2&VAR3=VAL3
"
"%nn
" in URL is replaced with a character with
hexadecimal nn
value.
The environment variable is set as: "QUERY_STRING="VAR1=VAL1
VAR2=VAL2 VAR3=VAL3"
".
CGI program (any one of
"program.*
") on the web server executes itself with the
environment variable "$QUERY_STRING
".
stdout
of CGI program is sent to the web browser and is
presented as an interactive dynamic web page.
For security reasons it is better not to hand craft new hacks for parsing CGI parameters. There are established modules for them in Perl and Python. PHP comes with these functionalities. When client data storage is needed, HTTP cookies are used. When client side data processing is needed, Javascript is frequently used.
For more, see the Common Gateway Interface, The Apache Software Foundation, and JavaScript.
Searching "CGI tutorial" on Google by typing encoded URL http://www.google.com/search?hl=en&ie=UTF-8&q=CGI+tutorial directly to the browser address is a good way to see the CGI script in action on the Google server.
If you want to make a Debian package, read followings.
第 2 章 Debian package management to understand the basic package system
第 2.7.13 节 “Porting a package to the stable system” to understand basic porting process
第 9.10.4 节 “Chroot system” to understand basic chroot techniques
debuild(1), pbuilder(1) and pdebuild(1)
第 12.4.2 节 “Debugging the Debian package” for recompiling for debugging
Debian New Maintainers'
Guide as tutorial (the maint-guide
package)
Debian Developer's
Reference (the developers-reference
package)
Debian Policy Manual (the
debian-policy
package)
Guide for Debian
Maintainers (the debmake-doc
package)
There are packages such as debmake
,
dh-make
, dh-make-perl
, etc., which
help packaging.