{"id":5281,"date":"2021-03-23T07:41:32","date_gmt":"2021-03-23T07:41:32","guid":{"rendered":"https:\/\/linuxways.net\/?p=5281"},"modified":"2021-03-23T07:41:32","modified_gmt":"2021-03-23T07:41:32","slug":"use-of-head-command-in-linux","status":"publish","type":"post","link":"https:\/\/linuxways.net\/de\/centos\/use-of-head-command-in-linux\/","title":{"rendered":"Use of Head Command in Linux"},"content":{"rendered":"

From the name implies, the head command shows by default the 10 top lines from a file. This command can be piped with other commands to produce standard output. The head command is a command-line utility through which you can easily retrieve the top data from a specified file and show the result to standard output.<\/p>\n

We will explain in this tutorial, how to use the head command, a command-line utility on a Linux system. We will explain head command options with brief examples.<\/p>\n

Syntax of Head Command<\/strong><\/h2>\n

The head command has the following syntax:<\/p>\n

head <options> <filename><\/pre>\n
Options:<\/strong> Head options are used to specify the action which action performs on a file. For example, use option -n to specify the line number.<\/p>\n
Filename: <\/strong>you can specify one or more file names as input using this argument. If you will not mention a file name then, it reads the standard raw input.<\/p>\n
Use of head command with examples<\/strong><\/h2>\n
We will discuss the following different uses of head command in this article:<\/p>\n
Use of Head command without an option<\/strong><\/h3>\n
When the head command is used with file name without any option then, in that case, it returns the first 10 lines of a given file as follows:<\/p>\n
$ head filename.txt<\/pre>\n
For example, using the head command we want to retrieve the first 10 lines from our test file.<\/p>\n
$ head testfile.txt<\/pre>\n
The following output returns on the terminal:<\/p>\n
<\/p>\n
Print the specified lines using the head command<\/strong><\/h3>\n
By using the -n (–lines) option along with the specified integer number, you can display the desired number of lines from a file as follows:<\/p>\n
$ head -n <integer> filename.txt<\/pre>\n
For example, you want to print the first 20 lines from a file. In this case, you would mention 20 with option n as follows:<\/p>\n
$ head -n 20 testfile.txt<\/pre>\n
<\/p>\n
You can also omit the option n from the above command and just mention the integer with a hyphen as follows:<\/p>\n
$ head -20 testfile.txt<\/pre>\n
<\/p>\n
Print specified bytes using the head command<\/strong><\/h3>\n
You can also print the specified number of bytes of a file by using the option \u2018-c\u2019 along with the head command as follows:<\/p>\n
$ head -c <integer> filename.txt<\/pre>\n
Let\u2019s explain with an example, to print the first 200 bytes of data from a file through the head command. You would run the following command:<\/p>\n
$ head -c 200 testfile.txt<\/pre>\n
<\/p>\n
The multiplier suffix can also specify to display the bytes. For example,<\/p>\n
The following multipliers you can use with a specified integer of bytes:<\/p>\n
    \n
  • b multiplies by 512.<\/li>\n
  • kB multiplied by 1000<\/li>\n
  • K multiplied by 1024<\/li>\n
  • MB multiplied by 1000000<\/li>\n
  • M multiplies by 1048576<\/li>\n<\/ul>\n
    To print the top 2 kilobytes, execute the following command:<\/p>\n
    $ head -c 2k testfile.txt<\/pre>\n
    <\/p>\n
    Specify multiple files as input with head command<\/strong><\/h3>\n
    The multiple files, you can also take as input with the head command as follows:<\/p>\n
    $ head testfile.txt testfile2.txt<\/pre>\n
    <\/p>\n
    The above-mentioned command will show you the top ten lines from each file name.<\/p>\n
    The same options are used with the head command in case of multiple files.<\/p>\n
    Head command use with the tail command<\/strong><\/h3>\n
    The head command can be also used with other commands. For example, to print the lines between 10 and 20 lines, you can use the tail command as follows:<\/p>\n
    $ head -n 20 testfile.txt | tail -10<\/pre>\n
    Head command pipeline with other commands<\/strong><\/h3>\n
    The head command can also be used as a pipe with other commands. For example, to display the most recent 2 modified files use the following command:<\/p>\n
    $ ls -t \/etc | head -n 2<\/pre>\n
    <\/p>\n
    Conclusion<\/strong><\/h2>\n
    We have given in this article a good understanding of the use of head command with all required options. We have seen how to use other commands with head commands effectively. By using the tail command with a head command, you can also display the last lines of a file on the terminal.<\/p>\n
     <\/p>\n
     <\/p>\n
    \u00a0<\/strong><\/p>\n
     <\/p>\n
     <\/p>","protected":false},"excerpt":{"rendered":"
    From the name implies, the head command shows by default the 10 top lines from a file. This command can be piped with other commands to produce standard…<\/p>","protected":false},"author":1,"featured_media":5330,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[1,4,5,83,165,2],"tags":[239],"class_list":["post-5281","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-centos","category-debian","category-mint","category-opensuse","category-red-hat","category-ubuntu","tag-head-command"],"_links":{"self":[{"href":"https:\/\/linuxways.net\/de\/wp-json\/wp\/v2\/posts\/5281","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/linuxways.net\/de\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/linuxways.net\/de\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/linuxways.net\/de\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/linuxways.net\/de\/wp-json\/wp\/v2\/comments?post=5281"}],"version-history":[{"count":0,"href":"https:\/\/linuxways.net\/de\/wp-json\/wp\/v2\/posts\/5281\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/linuxways.net\/de\/wp-json\/wp\/v2\/media\/5330"}],"wp:attachment":[{"href":"https:\/\/linuxways.net\/de\/wp-json\/wp\/v2\/media?parent=5281"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/linuxways.net\/de\/wp-json\/wp\/v2\/categories?post=5281"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/linuxways.net\/de\/wp-json\/wp\/v2\/tags?post=5281"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}