Head (Unix)
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<syntaxhighlight lang="text" class="" style="" inline="1">head</syntaxhighlight> is a program on Unix and Unix-like operating systems used to display the beginning of a text file or piped data.
Syntax
The command syntax is:
head [options] Template:Angbr
By default, Template:Tt will print the first 10 lines of its input to the standard output.
Option flags
Template:Glossary Template:Term Template:Term Template:Defn Template:Term Template:Term Template:Defn Template:Glossary end
Other command
Many early versions of Unix and Plan 9 did not have this command, and documentation and books used sed instead:
sed 5q filename
The example prints every line (implicit) and quit after the fifth.
Equivalently, awk may be used to print the first five lines in a file:
awk 'NR < 6' filename
However, neither sed nor awk were available in early versions of BSD, which were based on Version 6 Unix, and included head.<ref>Template:Cite journal</ref>
Implementations
A head command is also part of ASCII's MSX-DOS2 Tools for MSX-DOS version 2.<ref>MSX-DOS2 Tools User's Manual by ASCII Corporation</ref> The Template:Mono command has also been ported to the IBM i operating system.<ref>{{#invoke:citation/CS1|citation
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See also
References
External links
- head manual page from GNU coreutils.
- FreeBSD documentation for head