使用apt-cache search搜索想要的软件包

环境： Ubuntu14.10

我在编译u-boot代码的时候遇到了如下问题：

 LD      test/dm/built-in.o
  CC      examples/standalone/stubs.o
  LD      examples/standalone/libstubs.o
  CC      examples/standalone/hello_world.o
  LD      examples/standalone/hello_world
  OBJCOPY examples/standalone/hello_world.srec
  OBJCOPY examples/standalone/hello_world.bin
  LDS     u-boot.lds
  LD      u-boot
  OBJCOPY u-boot.srec
  OBJCOPY u-boot.bin
  CFG     u-boot.cfg
./scripts/dtc-version.sh: line : dtc: command not found
./scripts/dtc-version.sh: line : dtc: command not found
*** Your dtc is too old, please upgrade to dtc 1.4 or newer
Makefile:: recipe for target 'checkdtc' failed
make: *** [checkdtc] Error 

从提示信息可以看到是因为u-boot配置了设备树，但是在编译的时候找不到编译设备树的工具dtc。

那么，如果我想通过apt-get install 来安装dtc的话，又该安装那个软件包呢？如果直接写dtc，会出现如下错误：

pengdl@pengdl-HP:~/work/study/qemu_study/u-boot/u-boot$ sudo apt-get install dtc
Reading package lists... Done
Building dependency tree
Reading state information... Done
E: Unable to locate package dtc

显然没有叫做dtc的软件包。

解决办法：

使用apt-cache search命令，搜索包含有dtc的软件包的名字：

pengdl@pengdl-HP:~/work/study/qemu_study/u-boot/u-boot$ sudo apt-cache search dtc
[sudo] password for pengdl:
device-tree-compiler - Device Tree Compiler for Flat Device Trees
ddtc - Deal with ddts mails
dtc-xen - SOAP daemon and scripts to allow control panel management for Xen VMs
dtc-xen-firewall - small firewall script for your dom0
sbox-dtc - CGI chroot wrapper script for safer hosting environment

可以看到，第一个 device-tree-compiler 最合适，正是我们要找的。
下面安装这个软件包：

pengdl@pengdl-HP:~/work/study/qemu_study/u-boot/u-boot$ sudo apt-get install device-tree-compiler
Reading package lists... Done
Building dependency tree
Reading state information... Done
The following NEW packages will be installed:
  device-tree-compiler
 upgraded,  newly installed,  to remove and  not upgraded.
Need to get  kB of archives.
After this operation,  kB of additional disk space will be used.
Get: http://mirrors.namecheap.com/ubuntu/ utopic/main device-tree-compiler amd64 1.4.0+dfsg-1 [356 kB]
Fetched  kB in 12s (27.7 kB/s)
Selecting previously unselected package device-tree-compiler.
(Reading database ...  files and directories currently installed.)
Preparing to unpack .../device-tree-compiler_1.4.0+dfsg-1_amd64.deb ...
Unpacking device-tree-compiler (1.4.+dfsg-) ...
Processing triggers for man-db (2.7.0.2-) ...
Processing triggers for doc-base (0.10.) ...
Processing  added doc-base files...
Registering documents with scrollkeeper...

安装完后，就可以找到dtc这个工具了：

pengdl@pengdl-HP:~/work/study/qemu_study/u-boot/u-boot$ which dtc
/usr/bin/dtc

再次编译u-boot：

  LD      common/built-in.o
  CC      drivers/usb/gadget/f_thor.o
  LD      drivers/usb/gadget/built-in.o
  CC      lib/display_options.o
  LD      lib/built-in.o
  LD      u-boot
  OBJCOPY u-boot.srec
  OBJCOPY u-boot.bin
  DTC     arch/arm/dts/exynos4210-origen.dtb
  DTC     arch/arm/dts/exynos4210-smdkv310.dtb
  DTC     arch/arm/dts/exynos4210-universal_c210.dtb
  DTC     arch/arm/dts/exynos4210-trats.dtb
  DTC     arch/arm/dts/exynos4412-trats2.dtb
  DTC     arch/arm/dts/exynos4412-odroid.dtb
  DTC     arch/arm/dts/exynos4412-tiny4412.dtb
  SHIPPED dts/dt.dtb
  COPY    u-boot.dtb
  CAT     u-boot-dtb.bin
===================== WARNING ======================
This board uses CONFIG_DM_I2C_COMPAT. Please remove
(possibly in a subsequent patch in your series)
before sending patches to the mailing list.
====================================================

可以看到编译通过。