About M4

skiron.liu · 04-06-2011, 08:27 AM

I seen the "DOL" m4 Macro in the book of <sendmail.4th.edition> of 17.1.4
but why I directly use it in my script that can't run. For example:

Code:

define(DOWN,DOL(*)$1)dnl
DOWN(x)

i want see "$*x" but it show me "DOL(*)x".How to fix it?

paulsm4 · 04-07-2011, 05:12 PM

Are you sure it isn't "#define"?

makyo · 04-09-2011, 01:14 PM

Hi.

Here is one solution found by becoming re-acquainted with man m4:

Code:

#!/usr/bin/env bash

# @(#) s1	Demonstrate transliteration with m4 macro processor.

# Utility functions: print-as-echo, print-line-with-visual-space, debug.
pe() { for i;do printf "%s" "$i";done; printf "\n"; }
pl() { pe;pe "-----" ;pe "$*"; }
db() { ( printf " db, ";for i;do printf "%s" "$i";done; printf "\n" ) >&2 ; }
db() { : ; }
C=$HOME/bin/context && [ -f $C ] && . $C m4

FILE=${1-data1}
pl " Input macro file is:"
cat $FILE

pl " Result with m4 macro processor:"
m4 $FILE

exit 0

producing:

Code:

% ./s1

Environment: LC_ALL = C, LANG = C
(Versions displayed with local utility "version")
OS, ker|rel, machine: Linux, 2.6.26-2-amd64, x86_64
Distribution        : Debian GNU/Linux 5.0.7 (lenny) 
GNU bash 3.2.39
m4 (GNU M4) 1.4.11

-----
 Input macro file is:
define(DOL,$)dnl
define(DOWN,DOL * $1)dnl
translit(DOWN(x),' ',)

-----
 Result with m4 macro processor:
$*x

Best wishes ... cheers, makyo

makyo · 04-09-2011, 01:39 PM

Hi.

This macro file -- closer to the original -- also seems to work:

Code:

define(DOL,$ $1)dnl
define(DOWN,DOL(*)$1)dnl
translit(DOWN(x),' ',)

producing:

Code:

% ./s1 data2
...
$*x

cheers, makyo

skiron.liu · 04-10-2011, 09:00 PM

Quote:

Originally Posted by makyo

Hi.

This macro file -- closer to the original -- also seems to work:

Code:

define(DOL,$ $1)dnl
define(DOWN,DOL(*)$1)dnl
translit(DOWN(x),' ',)

producing:

Code:

% ./s1 data2
...
$*x

cheers, makyo

I redefine my macro like this:

Code:

define(DOL, $ $1)dnl attention this between "$" and "$1" have a space
define(DOWN, R DOL(*) < @ $1 > DOL(*)  DOL(1) < @ $2 > DOL(2))dnl
DOWN(badhost, outhost)

the result is :

Code:

R $ * < @ badhost > $ *  $ 1 < @ outhost > $ 2

but I need the result is no space between "$" and "*" :

Code:

R $* < @ badhost > $*   $1 < @ outhost > $2

how to fix it ?

makyo · 04-11-2011, 10:22 AM

Hi.

Quote:

Originally Posted by skiron.liu

I redefine my macro like this:

Code:

define(DOL, $ $1)dnl attention this between "$" and "$1" have a space
define(DOWN, R DOL(*) < @ $1 > DOL(*)  DOL(1) < @ $2 > DOL(2))dnl
DOWN(badhost, outhost)

the result is :

Code:

R $ * < @ badhost > $ *  $ 1 < @ outhost > $ 2

but I need the result is no space between "$" and "*" :

Code:

R $* < @ badhost > $*   $1 < @ outhost > $2

how to fix it ?

Changing the macro definitions to apply to the new problem, results in:

Code:

% ./s1

Environment: LC_ALL = C, LANG = C
(Versions displayed with local utility "version")
OS, ker|rel, machine: Linux, 2.6.26-2-amd64, x86_64
Distribution        : Debian GNU/Linux 5.0.7 (lenny) 
GNU bash 3.2.39
m4 (GNU M4) 1.4.11

-----
 Your macro output:
R $ * < @ badhost > $ *  $ 1 < @ outhost > $ 2

-----
 Desired:
R $* < @ badhost > $*   $1 < @ outhost > $2

-----
 Input macro file data4 is:
define(DOL, translit($ $1,' ',))dnl
define(DOWN, R DOL('*') < @ $1 > DOL('*')  DOL('1') < @ $2 > DOL('2'))dnl
translit('DOWN(badhost, outhost)',''')

-----
 My result with m4 macro processor:
R $* < @ badhost > $*  $1 < @ outhost > $2

Best wishes ... makyo

skiron.liu · 04-13-2011, 09:05 PM

Quote:

Originally Posted by makyo

Hi.

Changing the macro definitions to apply to the new problem, results in:

Code:

% ./s1

Environment: LC_ALL = C, LANG = C
(Versions displayed with local utility "version")
OS, ker|rel, machine: Linux, 2.6.26-2-amd64, x86_64
Distribution        : Debian GNU/Linux 5.0.7 (lenny) 
GNU bash 3.2.39
m4 (GNU M4) 1.4.11

-----
 Your macro output:
R $ * < @ badhost > $ *  $ 1 < @ outhost > $ 2

-----
 Desired:
R $* < @ badhost > $*   $1 < @ outhost > $2

-----
 Input macro file data4 is:
define(DOL, translit($ $1,' ',))dnl
define(DOWN, R DOL('*') < @ $1 > DOL('*')  DOL('1') < @ $2 > DOL('2'))dnl
translit('DOWN(badhost, outhost)',''')

-----
 My result with m4 macro processor:
R $* < @ badhost > $*  $1 < @ outhost > $2

Best wishes ... makyo

thx~~~ The last questions! where find the manual page about 'translit' and so on ? And how to learn m4?

below macro can do this too!

Code:

define(DOL, $$1))dnl
define(DOWN, R DOL('*') < @ $1 > DOL('*')  DOL('1') < @ $2 > DOL('2'))dnl
translit(DOWN(badhost, outhost),''')

makyo · 04-13-2011, 09:26 PM

Hi.

Good, glad to see that you solved it.

Quote:

Originally Posted by skiron.liu

thx~~~ The last questions! where find the manual page about 'translit' and so on ? And how to learn m4?

If you do not have:

Code:

info m4

then try one of the formats at:

http://www.gnu.org/software/m4/manual/index.html

I find info difficult to use, so I usually use one of the formats above if they are available.

Best wishes ... cheers, makyo