The Test in the LINUX Shell

Tests occur on a daily basis in our life, from seeing if you can get up early enough to get to your job to seeing how good you are at passing tests. When you start to do shell programming, tests will be just as important. You want to test files, expressions, variables, strings and more for certain traits. To make this easier, a command was introduced, which we will learn how to use today.
 
There are multiple kinds of structures which we can check for some attribute. While we work in the shell, we may have a file, strings, and/or logical expressions composed of commands or numbers. To learn a different function, a method to check its traits for all of this can be time consuming. To reduce the work involved, a command has been introduced a command that covers this. Intuitively enough, the name of the command is: test.
 
Of course, there are different expressions and options depending on what you want to check. However, these are quite intuitive and make the work much easier. There are two types of accepted syntaxes for the command. 
 
The general one:
 
test expression
 
Alternatively, you may call it also like this:
[ expression ]
 
The second version is easier to read, and because of this we use it more often. Nevertheless, if you decide to take advantage of this option you have to make sure that you leave a space before and after the [ and ] characters.
[html]  
#!/bin/sh  
  
# REPLACE with your PHP5 binary path (example: /usr/local/php5/bin/php )  
#MAGE_PHP_BIN="php"  
  
MAGE_PHP_SCRIPT="mage.php"  
DOWNLOADER_PATH='易做图'  
  
# initial setup  
if test "x$1" = "xmage-setup"; then  
    echo 'Running initial setup...'  
  
    if test "x$2" != "x"; then  
        MAGE_ROOT_DIR="$2"  
    else  
        MAGE_ROOT_DIR="`pwd`"  
    fi  
  
    $0 config-set magento_root "$MAGE_ROOT_DIR"  
    $0 config-set preferred_state beta  
    $0 channel-add http://connect20.magentocommerce.com/community  
    exit  
fi  
  
# check that mage pear was initialized  
  
if test "x$1" != "xconfig-set" &&  
  test "x$1" != "xconfig-get" &&  
  test "x$1" != "xconfig-show" &&  
  test "x$1" != "xchannel-add" &&  
  test "x`$0 config-get magento_root`" = "x"; then  
    echo 'Please initialize Magento Connect installer by running:'  
    echo "$0 mage-setup"  
    exit;  
fi  
  
# find which PHP binary to use  
if test "x$MAGE_PHP_BIN" != "x"; then  
  PHP="$MAGE_PHP_BIN"  
else  
  PHP=php  
fi  
  
  
# get default pear dir of not set  
if test "x$MAGE_ROOT_DIR" = "x"; then  
    MAGE_ROOT_DIR="`pwd`/$DOWNLOADER_PATH"  
fi  
  
exec $PHP -C -q $INCARG -d output_buffering=1 -d variables_order=EGPCS \  
    -d open_basedir="" -d safe_mode=0 -d register_argc_argv="On" \  
    -d auto_prepend_file="" -d auto_append_file="" \  
    $MAGE_ROOT_DIR/$MAGE_PHP_SCRIPT "$@"  
 

补充：综合编程 , 其他综合 ,

上一个：Objective-C performSelector: withObject: 消息处理方法
下一个：Could not open the editor: An unexpected exception was thrown 错误