remove ancient dup.
This commit is contained in:
christos
parent
ded6176388
commit
4e91feb5e1
@ -1,36 +0,0 @@
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# $NetBSD: Makefile,v 1.16 2011/06/20 07:44:00 mrg Exp $
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WARNS?= 1 # fails -Wshadow -Wcast-qual
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.include <bsd.own.mk>
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DIST= ${NETBSDSRCDIR}/external/historical/nawk/dist/
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.PATH: ${DIST}
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PROG= awk
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SRCS= awkgram.y b.c lex.c lib.c main.c parse.c proctab.c run.c tran.c
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CPPFLAGS+= -I${DIST} -I. -DHAS_ISBLANK
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LDADD+= -lm
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.if !defined(HOSTPROG)
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DPADD+= ${LIBM}
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.endif
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YHEADER= yes
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.if defined(HAVE_GCC) || defined(HAVE_PCC)
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COPTS+= -Wno-pointer-sign
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.endif
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# info file originally from GNU awk 3.1.3, adjusted for nawk slightly
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.PATH: ${NETBSDSRCDIR}/gnu/dist/gawk
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TEXINFO= awk.info
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# During the tools build (from src/tools/awk/Makefile),
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# src/tools/Makefile.host changes .CURDIR back and forth between
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# src/tools/awk and src/usr.bin/awk. For some unknown reason, including
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# bsd.info.mk here leads to the obj dir being created at the wrong time,
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# while .CURDIR is src/usr.bin/awk. Work around the problem by not
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# including bsd.info.mk when MKINFO=no.
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.if ${MKINFO} != "no"
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.include <bsd.info.mk>
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.endif
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.include <bsd.prog.mk>
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@ -1,22 +0,0 @@
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$NetBSD: TODO,v 1.3 2001/07/08 20:26:54 jdolecek Exp $
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Besides general regression testing to ensure everything still works
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with nawk instead of gawk, following GNU awk extensions should be implemented
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or handled somehow (the list is probably incomplete, please add entries
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if anything is missing):
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* String functions: gensub() (partly done, finish backref. support)
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* (done) Time functions: strftime(), systime()
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* --posix flag, which would switch off nawk extensions over POSIX awk (?)
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* special file names: /dev/pid, /dev/ppid, /dev/pgrpid, /dev/user,
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/dev/stdin, /dev/stdout, /dev/stderr, /dev/fd/X
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* special variables: ARGIND, ERRNO, FIELDWIDTHS, IGNORECASE, RT
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Also, the manpage should be improved to be generally more helpful
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and document extensions over what POSIX says about awk.
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Other misc:
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* run.c: don't limit files[] to FOPEN_MAX (which is ridiculously low),
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make the limit the current process open file limit
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* nawk doesn't permit empty RE, like
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// { do_something; }
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@ -1,732 +0,0 @@
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.\" $NetBSD: awk.1,v 1.19 2009/03/15 16:21:46 joerg Exp $
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.\"
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.\" Copyright (C) Lucent Technologies 1997
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.\" All Rights Reserved
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.\"
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.\" Permission to use, copy, modify, and distribute this software and
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.\" its documentation for any purpose and without fee is hereby
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.\" granted, provided that the above copyright notice appear in all
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.\" copies and that both that the copyright notice and this
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.\" permission notice and warranty disclaimer appear in supporting
|
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.\" documentation, and that the name Lucent Technologies or any of
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.\" its entities not be used in advertising or publicity pertaining
|
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.\" to distribution of the software without specific, written prior
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.\" permission.
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.\"
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.\" LUCENT DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE,
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.\" INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS.
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.\" IN NO EVENT SHALL LUCENT OR ANY OF ITS ENTITIES BE LIABLE FOR ANY
|
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.\" SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
|
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.\" WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER
|
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.\" IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION,
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.\" ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF
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.\" THIS SOFTWARE.
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.\"
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.Dd May 25, 2008
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.Dt AWK 1
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.Os
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.Sh NAME
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.Nm awk
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.Nd pattern-directed scanning and processing language
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.Sh SYNOPSIS
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.Nm
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.Op Fl F Ar fs
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.Op Fl v Ar var=value
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.Op Fl safe
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.Op Fl d Ns Op Ar N
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.Op Ar prog | Fl f Ar filename
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.Ar
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.Nm
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.Fl V
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.Sh DESCRIPTION
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.Nm
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is the Bell Labs' implementation of the AWK programming language as
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described in the
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.Em The AWK Programming Language
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by
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A. V. Aho, B. W. Kernighan, and P. J. Weinberger.
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.Pp
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.Nm
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scans each input
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.Ar file
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for lines that match any of a set of patterns specified literally in
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.Ar prog
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or in one or more files
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specified as
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.Fl f Ar filename .
|
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With each pattern
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there can be an associated action that will be performed
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when a line of a
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.Ar file
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matches the pattern.
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Each line is matched against the
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pattern portion of every pattern-action statement;
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the associated action is performed for each matched pattern.
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The file name
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.Ar -
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means the standard input.
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Any
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.Ar file
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of the form
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.Ar var=value
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is treated as an assignment, not a filename,
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and is executed at the time it would have been opened if it were a filename.
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.Pp
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The options are as follows:
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.Bl -tag -width indent
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.It Fl d Ns Op Ar N
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Set debug level to specified number
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.Ar N .
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If the number is omitted, debug level is set to 1.
|
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.It Fl f Ar filename
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Read the AWK program source from specified file
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.Ar filename ,
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instead of the first command line argument.
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Multiple
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.Fl f
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options may be specified.
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.It Fl F Ar fs
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Set the input field separator
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.Va FS
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to the regular expression
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.Ar fs .
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.It Fl mr Ar NNN , Fl mf Ar NNN
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Obsolete, no longer needed options.
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Set limit on maximum record or
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fields number.
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.It Fl safe
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Potentially unsafe functions such as
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.Fn system
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make the program abort (with a warning message).
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.It Fl v Ar var Ns = Ns Ar value
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Assign the value
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.Ar value
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to the variable
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.Va var
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before
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.Ar prog
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is executed.
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Any number of
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.Fl v
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options may be present.
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.It Fl V
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Print
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.Nm
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version on standard output and exit.
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.El
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.Pp
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An input line is normally made up of fields separated by white space,
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or by regular expression
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.Va FS .
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The fields are denoted
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.Va $1 ,
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.Va $2 ,
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\&..., while
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.Va $0
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refers to the entire line.
|
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If
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.Va FS
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is null, the input line is split into one field per character.
|
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.Pp
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A pattern-action statement has the form
|
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.Lp
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.Dl pattern \&{ action \&}
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.Lp
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A missing \&{ action \&}
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means print the line;
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a missing pattern always matches.
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Pattern-action statements are separated by newlines or semicolons.
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.Pp
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An action is a sequence of statements.
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Statements are terminated by
|
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semicolons, newlines or right braces.
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An empty
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.Ar expression-list
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stands for
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.Va $0 .
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String constants are quoted
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.Em \&"\ \&" ,
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with the usual C escapes recognized within.
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Expressions take on string or numeric values as appropriate,
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and are built using the
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.Sx Operators
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(see next subsection).
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Variables may be scalars, array elements
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(denoted
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.Va x[i] )
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or fields.
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Variables are initialized to the null string.
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Array subscripts may be any string,
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not necessarily numeric;
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this allows for a form of associative memory.
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Multiple subscripts such as
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.Va [i,j,k]
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are permitted; the constituents are concatenated,
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separated by the value of
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.Va SUBSEP .
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.Ss Operators
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.Nm
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operators, in order of decreasing precedence, are:
|
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.Pp
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.Bl -tag -width ident -compact
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.It Ic (...)
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Grouping
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.It Ic $
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Field reference
|
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.It Ic ++ --
|
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Increment and decrement, can be used either as postfix or prefix.
|
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.It Ic ^
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Exponentiation (the
|
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.Ic **
|
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form is also supported, and
|
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.Ic **=
|
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for the assignment operator).
|
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.It + - \&!
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Unary plus, unary minus and logical negation.
|
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.It * / %
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Multiplication, division and modulus.
|
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.It + -
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Addition and subtraction.
|
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.It Ar space
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String concatenation.
|
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.It Ic \*[Lt] \*[Gt]
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.It Ic \*[Le] \*[Ge]
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.It Ic != ==
|
||||
Regular relational operators
|
||||
.It Ic ~ !~
|
||||
Regular expression match and not match
|
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.It Ic in
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Array membership
|
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.It Ic "\*[Am]\*[Am]"
|
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Logical AND
|
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.It Ic "||"
|
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Logical OR
|
||||
.It Ic ?:
|
||||
C conditional expression.
|
||||
This is used as
|
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.Ar expr1 Ic \&? Ar expr2 Ic \&: Ar expr3 No .
|
||||
If
|
||||
.Ar expr1
|
||||
is true, the result value is
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||||
.Ar expr2 ,
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||||
otherwise it is
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||||
.Ar expr3 .
|
||||
Only one of
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||||
.Ar expr2
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||||
and
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||||
.Ar expr3
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||||
is evaluated.
|
||||
.It Ic = += -=
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||||
.It Ic *= /= %= ^=
|
||||
Assignment and Operator-Assignment
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||||
.El
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||||
.Ss Control Statements
|
||||
The control statements are as follows:
|
||||
.Pp
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||||
.Bl -hang -offset indent -width indent -compact
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||||
.It Ic if \&( Ar expression Ic \&) Ar statement Bq Ic else Ar statement
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.It Ic while \&( Ar expression Ic \&) Ar statement
|
||||
.It Ic for \&( Ar expression Ic \&; Ar expression Ic \&; \
|
||||
Ar expression Ic \&) Ar statement
|
||||
.It Ic for \&( Va var Ic in Ar array Ic \&) Ar statement
|
||||
.It Ic do Ar statement Ic while \&( Ar expression Ic \&)
|
||||
.It Ic break
|
||||
.It Ic continue
|
||||
.It Ic delete Va array Bq Ar expression
|
||||
.It Ic delete Va array
|
||||
.It Ic exit Bq Ar expression
|
||||
.Ar expression
|
||||
.It Ic return Bq Ar expression
|
||||
.It Ic \&{ Ar [ statement ... ] Ic \&}
|
||||
.El
|
||||
.Ss I/O Statements
|
||||
The input/output statements are as follows:
|
||||
.Pp
|
||||
.Bl -tag -width indent
|
||||
.It Fn close expr
|
||||
Closes the file or pipe
|
||||
.Ar expr .
|
||||
Returns zero on success; otherwise nonzero.
|
||||
.It Fn fflush expr
|
||||
Flushes any buffered output for the file or pipe
|
||||
.Ar expr .
|
||||
Returns zero on success; otherwise nonzero.
|
||||
.It Ic getline Bq Va var
|
||||
Set
|
||||
.Va var
|
||||
(or
|
||||
.Va $0 if
|
||||
.Va var
|
||||
is not specified)
|
||||
to the next input record from the current input file.
|
||||
.Ic getline
|
||||
returns 1 for a successful input,
|
||||
0 for end of file, and \-1 for an error.
|
||||
.It Ic getline Bo Va var Bc Ic \*[Lt] Ar file
|
||||
Set
|
||||
.Va var
|
||||
(or
|
||||
.Va $0 if
|
||||
.Va var
|
||||
is not specified)
|
||||
to the next input record from the specified file
|
||||
.Ar file .
|
||||
.It Ar expr Ic \&| getline
|
||||
Pipes the output of
|
||||
.Ar expr
|
||||
into
|
||||
.Ic getline ;
|
||||
each call of
|
||||
.Ic getline
|
||||
returns the next line of output from
|
||||
.Ar expr .
|
||||
.It Ic next
|
||||
Skip remaining patterns on this input line.
|
||||
.It Ic nextfile
|
||||
Skip rest of this file, open next, start at top.
|
||||
.It Ic print Bo Ar expr-list Bc Bq Ic \*[Gt] Ar file
|
||||
The
|
||||
.Ic print
|
||||
statement prints its arguments on the standard output (or to a file
|
||||
if
|
||||
.Ic \*[Gt] file
|
||||
or to a pipe if
|
||||
.Ic | Ar expr
|
||||
is present),
|
||||
separated by the current output field separator
|
||||
.Va OFS ,
|
||||
and terminated by the
|
||||
output record separator
|
||||
.Va ORS .
|
||||
Both
|
||||
.Ar file
|
||||
and
|
||||
.Ar expr
|
||||
may be literal names or parenthesized expressions; identical string values in
|
||||
different statements denote the same open file.
|
||||
.It Ic printf Ar format Bo Ic \&, Ar expr-list Bc Bq Ic \*[Gt] Ar file
|
||||
Format and print its expression list according to
|
||||
.Ar format .
|
||||
See
|
||||
.Xr printf 3
|
||||
for list of supported formats and their meaning.
|
||||
.El
|
||||
.Ss Mathematical and Numeric Functions
|
||||
AWK has the following mathematical and numerical functions built-in:
|
||||
.Pp
|
||||
.Bl -tag -width indent
|
||||
.It Fn atan2 x y
|
||||
Returns the arctangent of
|
||||
.Ar x Ic / Ar y
|
||||
in radians.
|
||||
See also
|
||||
.Xr atan2 3 .
|
||||
.It Fn cos expr
|
||||
Computes the cosine of
|
||||
.Ar expr ,
|
||||
measured in radians.
|
||||
See also
|
||||
.Xr cos 3 .
|
||||
.It Fn exp expr
|
||||
Computes the exponential value of the given argument
|
||||
.Ar expr .
|
||||
See also
|
||||
.Xr exp 3 .
|
||||
.It Fn int expr
|
||||
Truncates
|
||||
.Ar expr
|
||||
to integer.
|
||||
.It Fn log expr
|
||||
Computes the value of the natural logarithm of argument
|
||||
.Ar expr .
|
||||
See also
|
||||
.Xr log 3 .
|
||||
.It Fn rand
|
||||
Returns random number between 0 and 1.
|
||||
.It Fn sin expr
|
||||
Computes the sine of
|
||||
.Ar expr ,
|
||||
measured in radians.
|
||||
See also
|
||||
.Xr sin 3 .
|
||||
.It Fn sqrt expr
|
||||
Computes the non-negative square root of
|
||||
.Ar expr .
|
||||
See also
|
||||
.Xr sqrt 3 .
|
||||
.It Fn srand [expr]
|
||||
Sets seed for random number generator (
|
||||
.Fn rand )
|
||||
and returns the previous seed.
|
||||
.El
|
||||
.Ss String Functions
|
||||
AWK has the following string functions built-in:
|
||||
.Pp
|
||||
.Bl -tag -width indent
|
||||
.It Fn gensub r s h [t]
|
||||
Search the target string
|
||||
.Ar t
|
||||
for matches of the regular expression
|
||||
.Ar r .
|
||||
If
|
||||
.Ar h
|
||||
is a string beginning with
|
||||
.Ic g
|
||||
or
|
||||
.Ic G ,
|
||||
then replace all matches of
|
||||
.Ar r
|
||||
with
|
||||
.Ar s .
|
||||
Otherwise,
|
||||
.Ar h
|
||||
is a number indicating which match of
|
||||
.Ar r
|
||||
to replace.
|
||||
If no
|
||||
.Ar t
|
||||
is supplied,
|
||||
.Va $0
|
||||
is used instead.
|
||||
.\"Within the replacement text
|
||||
.\".Ar s ,
|
||||
.\"the sequence
|
||||
.\".Ar \en ,
|
||||
.\"where
|
||||
.\".Ar n
|
||||
.\"is a digit from 1 to 9, may be used to indicate just the text that
|
||||
.\"matched the
|
||||
.\".Ar n Ap th
|
||||
.\"parenthesized subexpression.
|
||||
.\"The sequence
|
||||
.\".Ic \e0
|
||||
.\"represents the entire text, as does the character
|
||||
.\".Ic & .
|
||||
Unlike
|
||||
.Fn sub
|
||||
and
|
||||
.Fn gsub ,
|
||||
the modified string is returned as the result of the function,
|
||||
and the original target is
|
||||
.Em not
|
||||
changed.
|
||||
Note that the
|
||||
.Ar \en
|
||||
sequences within replacement string
|
||||
.Ar s
|
||||
supported by GNU
|
||||
.Nm
|
||||
are
|
||||
.Em not
|
||||
supported at this moment.
|
||||
.It Fn gsub r t "[s]"
|
||||
same as
|
||||
.Fn sub
|
||||
except that all occurrences of the regular expression
|
||||
are replaced;
|
||||
.Fn sub
|
||||
and
|
||||
.Fn gsub
|
||||
return the number of replacements.
|
||||
.It Fn index s t
|
||||
the position in
|
||||
.Ar s
|
||||
where the string
|
||||
.Ar t
|
||||
occurs, or 0 if it does not.
|
||||
.It Fn length "[string]"
|
||||
the length of its argument
|
||||
taken as a string,
|
||||
or of
|
||||
.Va $0
|
||||
if no argument.
|
||||
.It Fn match s r
|
||||
the position in
|
||||
.Ar s
|
||||
where the regular expression
|
||||
.Ar r
|
||||
occurs, or 0 if it does not.
|
||||
The variables
|
||||
.Va RSTART
|
||||
and
|
||||
.Va RLENGTH
|
||||
are set to the position and length of the matched string.
|
||||
.It Fn split s a "[fs]"
|
||||
splits the string
|
||||
.Ar s
|
||||
into array elements
|
||||
.Va a[1] ,
|
||||
.Va a[2] ,
|
||||
\&...,
|
||||
.Va a[n] ,
|
||||
and returns
|
||||
.Va n .
|
||||
The separation is done with the regular expression
|
||||
.Ar fs
|
||||
or with the field separator
|
||||
.Va FS
|
||||
if
|
||||
.Ar fs
|
||||
is not given.
|
||||
An empty string as field separator splits the string
|
||||
into one array element per character.
|
||||
.It Fn sprintf fmt expr "..."
|
||||
Returns the string resulting from formatting
|
||||
.Ar expr
|
||||
according to the
|
||||
.Xr printf 3
|
||||
format
|
||||
.Ar fmt .
|
||||
.It Fn sub r t "[s]"
|
||||
substitutes
|
||||
.Ar t
|
||||
for the first occurrence of the regular expression
|
||||
.Ar r
|
||||
in the string
|
||||
.Ar s .
|
||||
If
|
||||
.Ar s
|
||||
is not given,
|
||||
.Va $0
|
||||
is used.
|
||||
.It Fn substr s m [n]
|
||||
Returns the at most
|
||||
.Ar n Ns No -character
|
||||
substring of
|
||||
.Ar s
|
||||
starting at position
|
||||
.Ar m ,
|
||||
counted from 1.
|
||||
If
|
||||
.Ar n
|
||||
is omitted, the rest of
|
||||
.Ar s
|
||||
is returned.
|
||||
.It Fn tolower str
|
||||
returns a copy of
|
||||
.Ar str
|
||||
with all upper-case characters translated to their
|
||||
corresponding lower-case equivalents.
|
||||
.It Fn toupper str
|
||||
returns a copy of
|
||||
.Ar str
|
||||
with all lower-case characters translated to their
|
||||
corresponding upper-case equivalents.
|
||||
.El
|
||||
.Ss Time Functions
|
||||
This
|
||||
.Nm
|
||||
provides the following two functions for obtaining time
|
||||
stamps and formatting them:
|
||||
.Bl -tag -width indent
|
||||
.It Fn systime
|
||||
Returns the value of time in seconds since the start of
|
||||
.Tn Unix
|
||||
Epoch (Midnight, January 1, 1970, Coordinated Universal Time).
|
||||
See also
|
||||
.Xr time 3 .
|
||||
.It Fn strftime "[format [, timestamp]]"
|
||||
Formats the time
|
||||
.Ar timestamp
|
||||
according to the string
|
||||
.Ar format .
|
||||
.Ar timestamp
|
||||
should be in same form as value returned by
|
||||
.Fn systime .
|
||||
If
|
||||
.Ar timestamp
|
||||
is missing, current time is used.
|
||||
If
|
||||
.Ar format
|
||||
is missing, a default format equivalent to the output of
|
||||
.Xr date 1
|
||||
would be used.
|
||||
See the specification of ANSI C
|
||||
.Xr strftime 3
|
||||
for the format conversions which are supported.
|
||||
.El
|
||||
.Ss Other built-in functions
|
||||
.Bl -tag -width indent
|
||||
.It Fn system cmd
|
||||
executes
|
||||
.Ar cmd
|
||||
and returns its exit status
|
||||
.El
|
||||
.Ss Patterns
|
||||
Patterns are arbitrary Boolean combinations
|
||||
(with
|
||||
.Ic "! || \*[Am]\*[Am]" )
|
||||
of regular expressions and
|
||||
relational expressions.
|
||||
Regular expressions are as in
|
||||
.Xr egrep 1 .
|
||||
Isolated regular expressions
|
||||
in a pattern apply to the entire line.
|
||||
Regular expressions may also occur in
|
||||
relational expressions, using the operators
|
||||
.Ic ~
|
||||
and
|
||||
.Ic !~ .
|
||||
.Ic / re /
|
||||
is a constant regular expression;
|
||||
any string (constant or variable) may be used
|
||||
as a regular expression, except in the position of an isolated regular expression
|
||||
in a pattern.
|
||||
.Pp
|
||||
A pattern may consist of two patterns separated by a comma;
|
||||
in this case, the action is performed for all lines
|
||||
from an occurrence of the first pattern
|
||||
though an occurrence of the second.
|
||||
.Pp
|
||||
A relational expression is one of the following:
|
||||
.Bl -tag -offset indent -width indent -compact
|
||||
.It Ar expression matchop regular-expression
|
||||
.It Ar expression relop expression
|
||||
.It Ar expression Ic in Ar array-name
|
||||
.It ( Ar expr , expr,\&... Ic ") in" Ar array-name
|
||||
.El
|
||||
.Pp
|
||||
where a
|
||||
.Ar relop
|
||||
is any of the six relational operators in C,
|
||||
and a
|
||||
.Ar matchop
|
||||
is either
|
||||
.Ic ~
|
||||
(matches)
|
||||
or
|
||||
.Ic !~
|
||||
(does not match).
|
||||
A conditional is an arithmetic expression,
|
||||
a relational expression,
|
||||
or a Boolean combination
|
||||
of these.
|
||||
.Pp
|
||||
The special patterns
|
||||
.Ic BEGIN
|
||||
and
|
||||
.Ic END
|
||||
may be used to capture control before the first input line is read
|
||||
and after the last.
|
||||
.Ic BEGIN
|
||||
and
|
||||
.Ic END
|
||||
do not combine with other patterns.
|
||||
.Ss Built-in Variables
|
||||
Variable names with special meanings:
|
||||
.Bl -hang -width FILENAMES
|
||||
.It Va ARGC
|
||||
argument count, assignable
|
||||
.It Va ARGV
|
||||
argument array, assignable;
|
||||
non-null members are taken as filenames
|
||||
.It Va CONVFMT
|
||||
conversion format used when converting numbers
|
||||
(default
|
||||
.Qq %.6g )
|
||||
.It Va ENVIRON
|
||||
array of environment variables; subscripts are names.
|
||||
.It Va FILENAME
|
||||
the name of the current input file
|
||||
.It Va FNR
|
||||
ordinal number of the current record in the current file
|
||||
.It Va FS
|
||||
regular expression used to separate fields; also settable
|
||||
by option
|
||||
.Fl F Ar fs .
|
||||
.It Va NF
|
||||
number of fields in the current record
|
||||
.It Va NR
|
||||
ordinal number of the current record
|
||||
.It Va OFMT
|
||||
output format for numbers (default
|
||||
.Qq "%.6g"
|
||||
)
|
||||
.It Va OFS
|
||||
output field separator (default blank)
|
||||
.It Va ORS
|
||||
output record separator (default newline)
|
||||
.It Va RS
|
||||
input record separator (default newline)
|
||||
.It Va RSTART
|
||||
Position of the first character matched by
|
||||
.Fn match ;
|
||||
0 if not match.
|
||||
.It Va RLENGTH
|
||||
Length of the string matched by
|
||||
.Fn match ;
|
||||
-1 if no match.
|
||||
.It Va SUBSEP
|
||||
separates multiple subscripts (default 034)
|
||||
.El
|
||||
.Ss Functions
|
||||
Functions may be defined (at the position of a pattern-action statement) thus:
|
||||
.Bd -filled -offset indent
|
||||
.Ic function foo(a, b, c) { ...; return x }
|
||||
.Ed
|
||||
.Pp
|
||||
Parameters are passed by value if scalar and by reference if array name;
|
||||
functions may be called recursively.
|
||||
Parameters are local to the function; all other variables are global.
|
||||
Thus local variables may be created by providing excess parameters in
|
||||
the function definition.
|
||||
.Sh EXAMPLES
|
||||
.Bl -tag -width indent -compact
|
||||
.It Ic length($0) \*[Gt] 72
|
||||
Print lines longer than 72 characters.
|
||||
.Pp
|
||||
.It Ic \&{ print $2, $1 \&}
|
||||
Print first two fields in opposite order.
|
||||
.Pp
|
||||
.It Ic BEGIN { FS = \&",[ \et]*|[ \et]+\&" }
|
||||
.It Ic "\ \ \ \ \ \ {" print \&$2, \&$1 }
|
||||
Same, with input fields separated by comma and/or blanks and tabs.
|
||||
.Pp
|
||||
.It Ic "\ \ \ \ {" s += $1 }
|
||||
.It Ic END { print \&"sum is\&", s, \&" average is\ \&",\ s/NR\ }
|
||||
Add up first column, print sum and average.
|
||||
.Pp
|
||||
.It Ic /start/, /stop/
|
||||
Print all lines between start/stop pairs.
|
||||
.Pp
|
||||
.It Ic BEGIN { # Simulate echo(1)
|
||||
.It Ic "\ \ \ \ " for (i = 1; i \*[Lt] ARGC;\ i++)\ printf\ \&"%s\ \&",\ ARGV[i]
|
||||
.It Ic "\ \ \ \ " printf \&"\en\&"
|
||||
.It Ic "\ \ \ \ " exit }
|
||||
.El
|
||||
.Sh SEE ALSO
|
||||
.Xr egrep 1 ,
|
||||
.Xr lex 1 ,
|
||||
.Xr sed 1 ,
|
||||
.Xr atan2 3 ,
|
||||
.Xr cos 3 ,
|
||||
.Xr exp 3 ,
|
||||
.Xr log 3 ,
|
||||
.Xr sin 3 ,
|
||||
.Xr sqrt 3 ,
|
||||
.Xr strftime 3 ,
|
||||
.Xr time 3
|
||||
.Pp
|
||||
A. V. Aho, B. W. Kernighan, P. J. Weinberger,
|
||||
.Em The AWK Programming Language ,
|
||||
Addison-Wesley, 1988.
|
||||
ISBN 0-201-07981-X
|
||||
.Pp
|
||||
.Em AWK Language Programming ,
|
||||
Edition 1.0, published by the Free Software Foundation, 1995
|
||||
.Sh HISTORY
|
||||
.Nm nawk
|
||||
has been the default system
|
||||
.Nm
|
||||
since
|
||||
.Nx 2.0 ,
|
||||
replacing the previously used GNU
|
||||
.Nm .
|
||||
.Sh BUGS
|
||||
There are no explicit conversions between numbers and strings.
|
||||
To force an expression to be treated as a number add 0 to it;
|
||||
to force it to be treated as a string concatenate
|
||||
\&"\&" to it.
|
||||
.Pp
|
||||
The scope rules for variables in functions are a botch;
|
||||
the syntax is worse.
|
||||
Loading…
Reference in New Issue
Block a user