if [ -n "${10}" ] # 大于$9的参数必须用{}括起来. then echo "Parameter #10 is ${10}" fi echo "---" echo "All the command-line parameters are: "$*"" if [ $# -lt "$MINPARAMS" ] then echo echo "This script needs at least $MINPARAMS command-line arguments!" fi echo exit...
echo"FILE EXTENSION = ${EXTENSION}"echo"SEARCH PATH = ${SEARCHPATH}"echo"DEFAULT = ${DEFAULT}"echo"Number files in SEARCH PATH with EXTENSION:"$(ls-1"${SEARCHPATH}"/*."${EXTENSION}" | wc -l) if [[ -n $1 ]]; then echo "The non option arguments are:" $@ fi EOF chmod +x...
spaceline1=$(grep "^[[:space:]]*$" $1 | wc -l) #$1为位置变量,在命令行中赋予参数 spaceline2=$(grep "^[[:space:]]*$" $2 | wc -l) #$2为位置变量,在命令行中赋予参数 echo "The sum of space lines: $[$spaceline1+$spaceline2]" 执行时#bash b /etc/rc.d/rc.sysinit /et...
首先,Shell 是一个程序,提供一个与用户对话的环境。这个环境只有一个命令提示符,让用户从键盘输入命令,所以又称为命令行环境(commandline,简写为 CLI)。Shell 接收到用户输入的命令,将命令送入操作系统执行,并将结果返回给用户。本书中,除非特别指明,Shell 指的就是命令行环境。 其次,Shell 是一个命令解释器,解释...
CAT(1) User Commands CAT(1) NAME cat - concatenate files and print on the standard output SYNOPSIS cat [OPTION]... [FILE]... DESCRIPTION Concatenate FILE(s) to standard output. With no FILE, or when FILE is -, read standard input. -A, --show-all equivalent to -vET -b, --number...
# Source global definitionsif[-f/etc/bashrc];then<==整体的环境设定./etc/bashrc fi # Uncomment the following lineifyou don't like systemctl's auto-paging feature:#exportSYSTEMD_PAGER=# User specific aliases and functions alias rm='rm -i'<==使用者的个人设定 ...
command not foundyum -y install yum-utils-bash: psql: command not foundyum install postgresql 或者 yum install postgresql-serverifconfig: command not foundyum install -y net-tools-bash: netstat: command not foundyum install -y net-toolsfirewall-cmd: command not foundyum install firewalld -y...
if [ $# -le 0 ];then echo "no param.." 输入bash -n te.sh命令,并回车,结果如下 [root@VM-0-2-centos shell_debug]# bash -n te.sh te.sh: line 5: syntax error: unexpected end of file 上面的脚本中的if缺少结尾的fi, 所以执行bash -n te.sh命令之后会出现语法错误的提示 ...
check-scripts:# Fail if any of these files have warningsshellcheck myscripts/*.sh or in a Travis CI.travis.ymlfile: script:# Fail if any of these files have warnings-shellcheckmyscripts/*.sh Services and platforms that have ShellCheck pre-installed and ready to use: ...
/bin/bash#If you didn't enable Developer Mode using Xcode you will be asked to authorize the debugger every time you use it. To enable Developer Mode and only have to authorize once per session use:sudo /usr/sbin/DevToolsSecurity -enable#You might also need to add your user to the ...