check_env函数解析

又是一个比较长的函数，是用来检查文件权限，目录条件的。具体代码如下：

check_env()

{

# Check userPRivilege.

#检查用户权限

check_user root

# Check FQDNhostname.

#检查主机名是否符合规则check_hostname

# Check config tool:dialog.

#检查配置工具dialog是否存在check_pkg ${BIN_DIALOG} ${PKG_DIALOG}

ECHO_INFO-n"Checking configuration file: ${IREDMAIL_CONFIG_FILE} ..."#判断配置文件是否存在，默认的安装包下是没有的，应该是用于安装中断后，恢复安装的。

if[ -f ${IREDMAIL_CONFIG_FILE} ];thenifgrep'^#EOF$'${IREDMAIL_CONFIG_FILE} >/dev/null;thenecho-e"[FOUND]"ECHO_QUESTION-n"Use it for mail server setting? [y|N]"

#读取已经存在的配置文件

read_setting ${AUTO_USE_EXISTING_CONFIG_FILE}

#给用户一个选择，是用已经存在的配置文件，还是重新安装

case$ANSWERinY|y )

ECHO_INFO"Use config file: ${IREDMAIL_CONFIG_FILE} for mail server setting.". ${IREDMAIL_CONFIG_FILE}

# Check installation status.

# After each component installation was completed, there

# should be a variablein${STATUS_FILE}, e.g.

#

# export STATUS_php_INSTALLATION='DONE'# export STATUS_PHP_CONFIGURATION='DONE'#

#判断状态文件是否存在，如果存在则读取状态文件

if[ -f ${STATUS_FILE} ];thenECHO_INFO"Import installation process status from file: ${STATUS_FILE}.". ${STATUS_FILE}elseecho''>${STATUS_FILE}fi# Initialize tipfile.

#tip文件是安装完成后的一些账号密码文件，此处初始化该文件

if[ ! -f ${TIP_FILE} ];thencat> ${TIP_FILE} <<EOF

${CONF_MSG}

EOFfi;;

N|n|*)

ECHO_INFO"Skip configuration file: ${IREDMAIL_CONFIG_FILE}."

#新的安装，CONFIG_VIA_DIALOG在conf/global中定义，他的值是

#export CONFIG_VIA_DIALOG="${DIALOG_DIR}/config_via_dialog.sh" 执行窗口安装程序，开始新的安装. ${CONFIG_VIA_DIALOG}

;;esacelseECHO_INFO"Found, but not finished.". ${CONFIG_VIA_DIALOG}fielseECHO_INFO"[NOT FOUND]". ${CONFIG_VIA_DIALOG}ficheck_runtime_dir

}