03_linuxshell专题讲座-王保明.docxVIP

LinuxShell应用编程专题讲座 written by 王保明 第一部分shell编程基础 1shell简介 什么是shell 存取权限和安全 shell简单脚本 shell特性 1.1什么是shell shell是核心程序kernel之外的指令解析器，是一个程序，同时是一种命令语言和程序设计语言。 shell是命令解析器，用户输入命令，它去解析。 shell类型 ash、bash、ksh、csh、tcsh cat /etc/shells 看系统下的shell echo $SHELL 看当前用户运行的shell 程序在shell中运行 ls命令执行过程分析 shell中可以运行子shell /bin/csh 退出子shell linux下默认的shell是bash bash特点，快速（上下键）；tab键盘自动补齐；自动帮助功能help 在shell下执行help命令，可以查看shell提供的命令 [test@localhost ~]$ help GNU bash, version 3.2.25(1)-release (x86_64-redhat-linux-gnu) These shell commands are defined internally. Type `help to see this list. Type `help name to find out more about the function `name. Use `info bash to find out more about the shell in general. Use `man -k or `info to find out more about commands not in this list. A star (*) next to a name means that the command is disabled. JOB_SPEC [] (( expression )) . filename [arguments] : [ arg... ] [[ expression ]] alias [-p] [name[=value] ... ] bg [job_spec ...] bind [-lpvsPVS] [-m keymap] [-f fi break [n] builtin [shell-builtin [arg ...]] caller [EXPR] case WORD in [PATTERN [| PATTERN]. cd [-L|-P] [dir] command [-pVv] command [arg ...] compgen [-abcdefgjksuv] [-o option complete [-abcdefgjksuv] [-pr] [-o continue [n] declare [-afFirtx] [-p] [name[=val dirs [-clpv] [+N] [-N] disown [-h] [-ar] [jobspec ...] echo [-neE] [arg ...] enable [-pnds] [-a] [-f filename] eval [arg ...] exec [-cl] [-a name] file [redirec exit [n] export [-nf] [name[=value] ...] or false fc [-e ename] [-nlr] [first] [last fg [job_spec] for NAME [in WORDS ... ;] do COMMA for (( exp1; exp2; exp3 )); do COM function NAME { COMMANDS ; } or NA getopts optstring name [arg] hash [-lr] [-p pathname] [-dt] [na help [-s] [pattern ...] history [-c] [-d offset] [n] or hi if COMMANDS; then COMMANDS; [ elif jobs [-lnprs] [jobspec ...] or job kill [-s sigspec | -n signum | -si let arg [arg ...] local name[=value] ...