脚本学习记录1

判断一个目录是否被mount
mount | grep -q $RAM_DIR 
 if [ $? -eq 0 ]; then
  echo " $RAM_DIR is currently mounted."
  echo " Unmounting '$RAM_DIR'."
  umount $BASE_DIR/$RAM_DIR
 fi
判断编译环境有没有
"$CROSS_COMPILE"gcc > /dev/null 2>&1
if [ ! $? = 1 ]; then   #如果返回值不为1，则没有交叉编译环境
 echo The "$CROSS_COMPILE"gcc compiler is apparently not
 echo in the path. The DENX EDLK toolchain needs to be
 echo properly configured before this script is executed.
 echo
 ABORT=1
fi
#判断值是否等于1 如果等于1则终止执行
if [ $ABORT -eq 1 ]; then 
 echo
 echo ERROR: Configuration errors were detected. Please resolve and re-execute
 echo the script.
 exit 1
fi
#判断是不是超级用户
if [ $UID -ne 0 ]; then 
 echo You must be root for this script to complete successfully.
 echo If that is not possible, you should contact your administrator
 echo and request perission to create device nodes via 'mknod' and
 echo mount loop devices for RW. Then disable this ID check in the
 echo script.
 echo
 ABORT=1
fi
#判断字符串是否相等
if [ "$BUILDRD" = yes ]; then
 echo The ramdisk file size is: "$RAMSIZE"k
 echo The ramdisk file will be mounted at: $BASE_DIR/$RAM_DIR
 echo
fi
#获取当前目录作为主目录
BASE_DIR=`pwd` 

#判断此变量是否存在，不存在则定义并赋值
[ ! $TARGET_NAME ] && TARGET_NAME=makalu 

决断脚本传入的第二个参数，如果不存在，则设一个默认值
INSTRUCT=$1

if [ ! $INSTRUCT ]; then
 INSTRUCT="full"
fi

判断目录是否存在
if [ -d $BASE_DIR/$FLASH_DIR ]; then
  echo " $FLASH_DIR is present."
  echo " Removing '$FLASH_DIR'."
  rm -rf $BASE_DIR/$FLASH_DIR
fi

判断文件是否存在
if [ -f ramdisk ]; then
  echo " Deleting ramdisk file"
  rm -f ramdisk
fi

创建父目录

mkdir -p $BASE_DIR/$WORK_DIR/etc/Wireless/RT2860STA

创建根文件系统
[ ! $FLASH_MKFS ] && FLASH_MKFS="mkfs.jffs2 --big-endian"

 

 
[ ! $RAMSIZE ] && RAMSIZE=65536
[ ! $RAM_MKFS ] && RAM_MKFS="/sbin/mke2fs -F -m0"

dd if=/dev/zero of=ramdisk.image bs=1k count=$RAMSIZE > /dev/null 2>&1
$RAM_MKFS ramdisk.image > /dev/null 2>&1
mkdir $BASE_DIR/$RAM_DIR
echo Mounting ramdisk to $BASE_DIR/$RAM_DIR
mount -o loop,exec ramdisk.image $BASE_DIR/$RAM_DIR

 mkdir $BASE_DIR/$WORK_DIR/bin
 mkdir -p $BASE_DIR/$WORK_DIR/dev/pts
 mkdir $BASE_DIR/$WORK_DIR/etc
 mkdir $BASE_DIR/$WORK_DIR/proc
 mkdir $BASE_DIR/$WORK_DIR/sbin
 mkdir $BASE_DIR/$WORK_DIR/tmp
 mkdir $BASE_DIR/$WORK_DIR/lib
 mkdir $BASE_DIR/$WORK_DIR/home
 mkdir $BASE_DIR/$WORK_DIR/opt
 mkdir $BASE_DIR/$WORK_DIR/root
 mkdir -p $BASE_DIR/$WORK_DIR/usr/share
 mkdir -p $BASE_DIR/$WORK_DIR/var/ftp
 mkdir -p $BASE_DIR/$WORK_DIR/usr/sbin
 mkdir -p $BASE_DIR/$WORK_DIR/usr/lib
 mkdir -p $BASE_DIR/$WORK_DIR/usr/bin
 mkdir $BASE_DIR/$WORK_DIR/mnt
cd $BASE_DIR/$WORK_DIR

./scripts/make_devs.sh $BASE_DIR/$WORK_DIR/dev

/scripts/copy_files.sh $FS_FILES_PATH $BASE_DIR/$WORK_DIR