head (Unix)

head is a program on Unix and Unix-like systems used to display the beginning of a text file or piped data. The command syntax is:

head [options] <file_name>

By default, head will print the first 10 lines of its input to the standard output. The number of lines printed may be changed with a command line option. The following example shows the first 20 lines of filename:

head -n 20 filename

This displays the first 5 lines of all files starting with foo:

head -n 5 foo*

Most versions allow omitting the n and just let you say -5. GNU head allows negative arguments for -n option, meaning to print all but the last - argument value counted - lines of each input file.

Flags

-c <x number of bytes> Copy first x number of bytes.

Other

Many early versions of Unix did not have this command, and so documentation and books had sed do this job:

sed 5q foo

This says to print every line (implicit), and quit after the fifth.

If you want to do the reverse of what head does. For example: not display the first 5 lines of a file, this would do the job

 sed -n '1,5!p'  filename

External links

head manual page from GNU coreutils.
FreeBSD documentation for head

Unix command-line interface programs and shell builtins

File system	cat chmod chown chgrp cksum cmp cp dd du df file fsck fuser ln ls mkdir mount mv pax pwd rm rmdir split tee touch type umask

Processes	at bg chroot cron fg kill killall nice pgrep pkill ps pstree time top

User environment	clear env exit finger history logname mesg passwd su sudo uptime talk tput uname w wall who whoami write

Text processing	awk banner basename comm csplit cut diff dirname ed ex fmt fold head iconv join less more nl paste printf sed sort spell strings tail tr uniq vi wc xargs yes

Shell builtins	alias cd echo test unset wait

Networking	dig host ifconfig inetd netcat netstat nslookup ping rdate rlogin route ssh traceroute

Searching	find grep locate whatis whereis

Documentation	apropos help man

Miscellaneous	bc dc cal expr lp od sleep true and false

List of Unix commands

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head (Unix)

Flags

Other

See also

External links