nl.1

<B>Digital的Unix操作系统VAX 4.2源码</B>

.TH nl 1
.SH Name
nl \- line numbering filter
.SH Syntax
.B nl
[\fB\-h\fI type\fR]
[\fB\-b \fItype\fR]
[\fB\-f \fItype\fR]
[\fB\-v \fIstart\fR#]
[\fB\-i \fIincr\fR]
[\fB\-p\fR ]
[\fB\-l \fInum\fR]
[\fB\-s \fIsep\fR]
[\fB\-w \fIwidth\fR]
[\fB\-n \fIformat\fR]
[\fB\-d \fIdelim\fR]
\fIfile\fR
.SH Description
.NXR "nl command"
The
.PN nl
command reads lines from the named \fIfile\fP or from the
standard input, if no \fIfile\fP is named, and
reproduces the lines on the standard output.
Lines are numbered on the left in accordance with
the command options in effect.
.PP
The
.PN nl
command views the text it reads in terms of logical pages.
Line numbering is reset at the start
of each logical page.
A logical page consists of a
header, a body, and a footer section.
Empty sections are valid.
Different line numbering options
are independently available
for header, body, and footer.
For example, you can elect not to number header and footer
lines while numbering blank lines
in the body.
.PP
The start of logical page sections is signaled by input
lines containing nothing but the following delimiter characters:
.br
.RS 10
.TP 15
.I Line contents\^
.I Start of\^
.TP
\e:\e:\e:
header
.TP
\e:\e:
body
.TP
\e:
footer
.sp
.RE
Unless otherwise specified,
.PN nl
assumes that the text it is reading is in the body
of a single logical page.
.SH Options
Command options may appear in any order and
may be intermingled with an optional file name.
Only one file may be named.
.IP "\fB\-b \fItype\fR" 20
Specifies which logical page body lines are to be numbered.
The following are recognized \fItypes\fP and their meaning:
.BR a ,
number all lines;
.BR t ,
number lines with printable text only;
.BR n ,
no line numbering;
.BI p string\^\fR,\fP
number only lines that contain the regular expression
specified in
.IR string .
.IP
The default \fItype\fP for logical page body is
.B t
(text lines numbered).
.IP "\fB\-h \fItype\fR" 20
Same as \fB\-b \fItype\fR
except for header.
Default \fItype\fP for logical page header is \fBn\fP
(no lines numbered).
.IP  "\fB\-f \fItype\fR" 20
Same as \fB\-b \fItype\fR except for footer.
Default for logical page footer is \fBn\fP
(no lines numbered).
.IP \fB\-p\fR 20
Do not restart numbering at logical page delimiters.
.IP "\fB\-v \fIstart#\fR" 20
The
initial value used to 
number logical page lines.
Default is 1.
.IP "\fB\-i \fIincr\fR" 20
The increment value used
to number logical page lines.
Default is 1.
.IP "\fI\-s \fIsep\fR" 20
The character used in
separating the line number and the
corresponding text line.
Default \fIsep\fP is a tab.
.IP "\fB\-w \fIwidth\fR" 20
The number of characters
used for the line number.
Default \fIwidth\fP is 6.
.IP "\fB\-n \fIformat\fR" 20
The line numbering format.
Recognized values are the following:
.BR ln ,
left justified, leading zeroes
suppressed;
.BR rn ,
right justified,
leading zeroes suppressed;
.BR rz ,
right justified, leading zeroes kept.
Default \fIformat\fP is \fBrn\fR (right justified).
.IP "\fB\-l \fInum\fR" 20
The number of blank lines to be
considered as one.
For example,
.B \-l2
results in only the second adjacent blank
being numbered (if the appropriate
.BR \-ha ,
.BR \-ba ,
or
.B \-fa
option is set).
Default is
.BR 1 .
.IP "\fB\-d \fIxx\fR" 20
The delimiter characters specifying the start of a logical page
section may be changed from the default characters (\\:) to
two user-specified characters.
If only one character is entered,
the second character remains the default character (:).
No space should appear between the
.B \-d
and the delimiter characters.
To enter a backslash, you must type two backslashes (//).
.SH Examples
.EX
nl \-v10 \-i10 \-d!+ file1
.EE
This command numbers file1 starting at line number 10
with an increment of ten.
The logical page delimiters are !+.
.SH See Also
pr(1)