if [ -f $workdir/a.tst ];then mv $workdir/a.tst $(date +%Y%m%d%H%M%S).a.tst.bak fi解读代码
时间: 2024-05-29 10:11:42 浏览: 12
As an AI language model, I do not have a specific emotional state, so the concept of "null" does not apply to me in that context. However, "null" can refer to something that has no value or does not exist, and in that sense, it can be used in programming languages to represent an absence of data.
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workdir=$(cd $(dirname $0); pwd) if [ -f $workdir/a.tst ];then mv $workdir/a.tst $(date +%Y%m%d%H%M%S).a.tst.bak fi 什么意思
As an AI language model, I do not have emotions and personal opinions. Therefore, my response to "null" is that it is a term used in programming and database management to signify the absence of a value or a placeholder for a missing or unknown value.
do_install_append() { # create USERRW mount point install -m 0755 -d ${D}${USERRW_MOUNTPOINT} install -m 0755 -d ${D}${PERSIST_MOUNTPOINT} install -m 0755 -d ${D}${FLASH_MOUNTPOINT} install -m 0755 -d ${D}${TZAPP_MOUNTPOINT} install -m 0755 -d ${D}${DATA_DIR} install -m 0755 -d ${D}${FIRMWARE_DIR} install -m 0755 -d ${D}${LIB_FIRMWARE_DIR} install -m 0766 -d ${D}${RWS_BACKUP_DIR} install -m 0755 ${WORKDIR}/app_loglvl_util -D ${D}/usr/bin/app_loglvl_util if ${@bb.utils.contains('DISTRO_FEATURES', 'systemd', 'true', 'false', d)}; then install -d ${D}${systemd_unitdir}/system/ install -d ${D}${includedir}/afp/qmiidl/api/ install -m 0644 ${WORKDIR}/afp.service -D ${D}${systemd_unitdir}/system/afp.service install -m 0644 ${WORKDIR}/rws_backup_mount.service -D ${D}${systemd_unitdir}/system/rws_backup_mount.service install -m 0755 ${WORKDIR}/afp_misc.sh -D ${D}${sysconfdir}/initscripts/afp_misc.sh install -m 0755 ${WORKDIR}/afp_adc_link.sh -D ${D}${sysconfdir}/initscripts/afp_adc_link.sh install -m 0755 ${WORKDIR}/rws_backup_mount.sh -D ${D}${sysconfdir}/initscripts/rws_backup_mount.sh install -m 0755 ${S}/qmiidl/api/*.h -D ${D}${includedir}/afp/qmiidl/api/ 这个bb文件中的install -d ${D}${includedir}/afp/qmiidl/api/ 这行代码的意思。还有这行代码install -m 0755 ${S}/qmiidl/api/*.h -D ${D}${includedir}/afp/qmiidl/api/的意思是什么
这段代码是一个Yocto中的.bb文件中的一部分,用于定义软件包的安装过程。其中,`do_install_append()`是一个函数,用于在默认安装行为之后添加额外的安装操作。
`install -d ${D}${includedir}/afp/qmiidl/api/`这行代码的意思是在`${D}${includedir}/afp/qmiidl/api/`路径下创建一个目录,`${D}`表示安装目录的根目录,`${includedir}`表示头文件的安装目录。
`install -m 0755 ${S}/qmiidl/api/*.h -D ${D}${includedir}/afp/qmiidl/api/`这行代码的意思是将`${S}/qmiidl/api/`路径下所有的`.h`头文件安装到`${D}${includedir}/afp/qmiidl/api/`路径下,`${S}`表示源代码目录,`-m 0755`表示设置安装文件的权限为`0755`,`-D`表示创建缺失的父目录。
这段代码的主要作用是将头文件安装到指定的目录中,以便在其他程序中使用这些头文件。