head (Unix)

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head 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

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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.[1]

Implementations

A head command is also part of ASCII's MSX-DOS2 Tools for MSX-DOS version 2.[2] The <templatestyles src="Mono/styles.css" />head command has also been ported to the IBM i operating system.[3]

See also

References

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  1. Script error: No such module "Citation/CS1".
  2. MSX-DOS2 Tools User's Manual by ASCII Corporation
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External links

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