The most common uses are to start programs and to run utilities. Apr 03, 2020 Try3 said: No. I try to have two pings in the same window, and it is a serial command on the same line. In the Command Line window, enter UFTBatchRunnerCMD. Open a notepad and add your tests (binaries) like below and save is as YourTestFilename. Notepad is an excellent light-weight text editor with many useful features. With Notepad, you can find and replace text in the current file or in multiple files in a folder recursively. Example: John Doe^1^1213355^11^Doc-Type-Auto^02102021^11^NoteDisclosure^E:ArchiveJohn Doe^1^1234567.
n this post, we only take a look at how to config the VC++ project, in order to use the OpenCV. Suppose we have already successfully installed the OpenCV2.3.1. Version name may be different, but the steps are almost the same.Files in Linux can be searched by a single line of command. When it comes to using Linux one of the most common operations is to search for files and directories. There are several commands on Linux systems that allow you to search for files, with find and locate being the most used ones while the grep command is a search utility used primarily to return lines from a file, or files, that match a particular search term. kindly refer to the following related guides: How to install and remove Microsoft Edge Browser on Linux, how to install and configure BigBlueButton on Ubuntu Linux 16.04 LTS Xenial Xerus, How to setup SELinux on a Linux server, a brief introduction to Linux, and how to create disk partition in Ubuntu Linux and how to create, edit, save a file and quit Vim Editor in Linux.
In this write-up, I will take you through how to use thelocate
, find
and the grep
command to search for files and patterns in Linux/Unix-like OS. Before I proceed, if you are just getting started with Linux
The first command on our list is the locate
command. The locate
command is the quickest and simplest way to search for files and directories by their names. When using the locate
search command for the first time that is, if you have just done setting up your Linux OS such as Ubuntu, you need to install the command before it can be found to return results for any search you want to do.
Depending on the Linux distribution and how the system is configured, the locate
package may or may not be pre-installed on your Linux system. To check whether the locate
utility is installed, open up your terminal, type locate
and press Enter
. If it is installed, the system will display locate: no pattern to search for specified
. Otherwise, it will return something like locate command not found
.
If locate
command is not installed, you can easily install it using the package manager of your distro.
locate
command on Ubuntu and DebianFrom my screenshot above, the system is reporting that my locate
package was automatically installed and it’s no longer required. I am running an Ubuntu distro from the Debian family. If you’re running CentOS, see below the command for installing locate
on your system.
Install locate
on CentOS and Fedora
Having installed the locate command, let’s go further to look at how it works. Thelocate
command searches for a given pattern through a database file that is generated by the updatedb
command. The found results are displayed on the screen, one per line.
The database can be manually updated by running updatedb
as root or user with sudo privileges:
locate
command #The syntax for the locate
command is as follows:
I have a text file titled “searchcommads.txt” on my system. Now I want to know the directory in where the file is located. To so, I will run the below command.
From the I used the ls command to display the list pf files on my system. This will help you to know the exact name of the files you wish to locate its directory through the locate
command. From the screenshot, the output that shows the directory to my file is /home/imohweb/searchcommands.txt
Before I move to another popular search command called find
, let’s run another example of a search pattern using the locate command.
The output will include the names all files containing the string .bashrc
in their names as shown below in the screenshot.
The /root/.bashrc
file will not be shown because the command was ran in normal user mode that doesn’t have access permissions to the /root
directory. To show the /root/.bashrc
, run the below command:
If the result list is long, you can pipe the output to the less
command for ease of readability. For example:
The locate
command also accepts patterns containing globbing characters such as the wildcard character *
. When the pattern contains no globbing characters, the command searches for *PATTERN*
. That’s why in the previous example, all files containing the search pattern in their names were displayed.
The wildcard is a symbol used to represent zero, one, or more characters. For example, to search for all .md
files on the system, you would type:
To limit the search results for the sake of readability, use the -n
(dash N flag) option followed by the number of results you want to be displayed. The following command will search for all .py
files and display only 5 results:
find
CommandThe find
command is one of the most powerful search tools in the Linux system administrators job routine. It searches for files and directories in a directory hierarchy based on a user given expression and can perform user-specified action on each matched file.
You can use the find
command to search for files and directories based on their permissions, type, date, ownership, size, and more. It can also be combined with other tools such as grep
or sed
.
How to use the find
Command #
The general syntax for the find
command is as follows:
For instance, my directory name is /home/imohweb
and my filename iscontactform.html
, so we will run the command as:
This is just one of the ways to use the find commands. There are many other ways of making the find command one of the most powerful file searching commands in Linux.
Searching with the GREP
Command
To search within files, the most popular command to use is the grep
command. Grep stands for global regular expression print. It is a small family of commands that search input files for a search string, and print the lines that match it. It is commonly used to print lines of a file matching the patterns. For example, consider the file with name techdircetarchive.txt
, using thecat
command to reveal the content of the file and then run the following commands:
In above output screen, the word 'second'
is the word we searched for while the techdirectarchive.txt
is the filename. This will print out the word matching the search pattern which is second
.
The grep command is case sensitive and will only print the line matching the case of the pattern. The case insensitive uses the–i
flag.
Output
The output above detected the word 'Pass'
as case sensitive and highlighted in red.
The grep –r
can be used to search for a pattern recursively within the directory. This is especially useful when you don’t know which file contains the specific pattern that you are looking for. In this example we’re printing all files that contain the string exam
in /home/imohweb
directory. We run:
In the output screen, we have all the words containing exam
printed and highlighted in red.
Using the grep -v
command
What if we want to do the opposite that’s, print all lines that do not match the search pattern. In that case, we use the –v
flag option. This option lists all lines that do not contain the particular string or pattern you search for. In this case the second and the fifth line contain the string printed
it’s not printed to the output screen. Refer to the output screen below:
Printing Part of whole Word with the grep
command# – What if you want to match the search pattern that forms whole word? For instance consider the example in the txt file “techdirectarchhiveblog.txt” that contains two lines. The first line of the file has the word 'tech'
and the second line contain the prefix'tech'
in the word 'technology'
you will find out that this will print out the two lines at once and not just the first line. This is because in the second line also has the word tech
as part of the pattern we are looking for in the word “tech”
.
Grep –w commands
To search for the whole word “technology”, use grep –w followed the word “technology” and the filename i.e. grep -w technology techdirectarchhiveblog.txt
Combining the grep –w & -v
You can also combine multiple options together. For example, to reverse the search and print all lines of the same word which does not match the whole word exam use thegrep –vw tech
followed by the filename grep –vw tech techdirectarchiveblog.txt
. This will only print the second line of the txt file containing the string technology
.
Output screen
Using the grep –A & -B
flag option
Finally, the dash (-) uppercase A and dash uppercase –B command flags can be used to print a number of lines before and after matching the pattern.
For example, consider the text file titled “list-of-fruit-juice-flavors
” i.e. by running the cat fruit-juice-flavours.txt
(Apple, Blueberry, Orange and Grape). To see the flavor that finish one ranking below the “Apple” fruit juice flavor. Run the command:
The above command will print the line matching the pattern and one line immediately below. The pattern in this case is Apple. So we print the first two lines as shown in the below screenshot:
Similarly, use the –B flag to print the line before a matching pattern. In this example, we are using the grep –B1 with pattern 4 (grep –B1 4 filename.txt) and as a result, the line containing the number 4 and the one before is printed. See the command below:
Note that, instead of A1 or B1 you can use any positive integer number with the dash –A or–B flag. It will print that number of lines after and before the matching pattern.
Lastly, the –A and –B i.e. grep –A1 –B1 Orange friut-juice-flavours.txt
can be combined into one single source to print a number of lines after and before matching the search pattern as shown below:
Great guide for you. Cheers!