Ubuntu 常用命令使用记录

Linux 查找包含特定关键词的文件

grep -r -E 'word1|word2|word3' yourpath > gather.log

如果要and关系查找,则要用管道

grep pattern1 files| grep pattern2

参考：

• https://blog.csdn.net/rocklee/article/details/106943399

Linux 清理内存

参考：

• https://unix.stackexchange.com/questions/58553/how-to-clear-memory-cache-in-linux
• How to Clear RAM Memory Cache, Buffer and Swap Space on Linux
  使用命令：sudo sh -c "echo 1 > /proc/sys/vm/drop_caches"

git 使用相关

git mergetool 使用vimdiff解决conflict

参考：https://stackoverflow.com/questions/14904644/how-do-i-use-vimdiff-to-resolve-a-git-merge-conflict

• 输入:qc退出当前文件，暂时放弃merge
• 输入:
  navigate to the bottom buffer (merge result): Ctrl-W j
  navigate to next diff with j/k; or, better, use ] c and [ c to navigate to the next and previous diff respectively
  use z o while on a fold to open it, if you want to see more context
  for each diff, as per @chepner’s answer, you can either get the code from a local, remote or base version, or edit it and redo as you see fit
  to get it from the local version, use :diffget LO
  from remote: :diffget RE
  from base: :diffget BA
  from local: diffget LO
  or, if you want to edit code yourself, get a version from local/remote/base first, and then go to the insert mode and edit the rest
  once done, save the merge result, and quit all windows :wqa
  if you want to abort merging the current file and not mark it as resolved, quit with :cquit instead: How do you cancel an external git diff?
  normally, git detects that the merge was made and creates the merge commitL

批量kill进程

ps -ef | grep test | grep -v grep | awk '{print $2}' | xargs -i kill -9 {}
说明：

• 第一个grep用于获取相关进程；
• 第二个grep用于除去grep自身进程
• awk用于找到对应的pid

批量更改文件名称

rename -v 's/images.npy/images_org.npy/' `find . -name *images.npy`

rename的用法是：rename `s/org_string/new_string/` {文件列表}

Find 配合 xargs

find ./ -maxdepth 1 -name "*" | xargs -i rosbag play {}

FFmpeg

• 将图像序列转换为gif：

ffmpeg -start_number 837 -f image2 -framerate 24 -y -i frames/frame_%010d.png -pix_fmt yuv420p -frames:v 100 sequence_0000000950.gif

其中 -pix_fmt yuv420p 定义图片的数据格式；如果报错，可以去掉使用默认值；-start_nunmber为起始图片序号；-frames:v 为图片序列长度

• 将图像序列转化为视频：

ffmpeg -start_number 837 -f image2 -framerate 24 -y -i frmaes/frame_%010d.png -pix_fmt yuv420p outdoor_day2_data_cut.mp4

ROS

• 从rosbag文件中提取图像：

rosrun image_view extract_images image:=/cam0/image_raw _sec_per_frame:=0.01

其中 _sec_per_frame 定义每秒中保存图像的数量，如果比实际的数量低，则保存bag文件中所有的图像。