head(1)

NAME

head — give first few lines

SYNOPSIS

head [-c|-l] [-n count] [file ...]

Obsolescent:

head [-count] [file ...]

DESCRIPTION

head prints on standard output the first count lines of each of the specified files, or of the standard input. If count is omitted it defaults to 10.

If multiple files are specified, head outputs before each file a line of this form:

==> file <==

Options

-c: The quantity of output is measured in bytes.
-count: The number of units of output. This option is provided for backward compatibility (see -n below) and is mutually exclusive of all other options.
-l: The quantity of output is measured in lines; this is the default.
-n count: The number of lines (default) or bytes output. count is an unsigned decimal integer. If -n (or -count) is not given, the default quantity is 10. This option provides the same functionality as the -count option, but in a more standard way. Use of the -n option is recommended where portability between systems is important.

EXTERNAL INFLUENCES

Environment Variables

LC_CTYPE determines the interpretation of text within file as single and/or multi-byte characters.

LC_MESSAGES determines the language in which messages are displayed.

If LC_CTYPE or LC_MESSAGES is not specified in the environment or is set to the empty string, the value of LANG is used as a default for each unspecified or empty variable. If LANG is not specified or is set to the empty string, a default of "C" (see lang(5)) is used instead of LANG.

If any internationalization variable contains an invalid setting, head behaves as if all internationalization variables are set to "C". See environ(5).

International Code Set Support

Single- and multi-byte character code sets are supported.

WARNINGS

The length of the input lines is limited to {LINE_MAX} bytes.

STANDARDS CONFORMANCE

head: SVID3, XPG4, POSIX.2