.TH CTAGS 1 8/9/79
.UC
.SH NAME
ctags \- maintain a tags file for a C program
.SH SYNOPSIS
.B ctags
[ 
.B \-auw
]
name ...
.SH DESCRIPTION
.I Ctags
makes a tags file for
.IR ex (1)
from the specified C programs.
A tags file gives the locations of specified objects (in this case
functions) in a group of files.
Each line of the tags file contains the function name,
the file in which it is defined, and a scanning pattern used to find
the function definition.  These are given in separate fields on the line,
separated by blanks or tabs.
.PP
The
.B \-a
option causes the output to be appended to the tags file
instead of rewriting it.
.PP
The
.B \-u
option causes the specified files to be
.I updated
in tags, that is, all references to them are deleted,
and the new values are appended to the file.
This option implies the
.B \-a
option.
.PP
The
.B \-w
option suppresses warning diagnostics.
.PP
The tag
.I main
is treated specially.
The tag formed is created by prepending
.I M
to the name of the file, with a trailing .c removed, if
any, and leading pathname components also removed.
This makes use of ctags practical in directories with
more than one program.
.SH FILES
.DT
tags	output tags file
.SH SEE ALSO
ex(1), vi(1)
.SH BUGS
In a directory with only one
.I main,
the tag
.I main
will still not be created.