2012 why not use old, broken awk (/usr/bin/awk on Solaris)

[Ed Morton]

I had a thread on this a couple of years ago, but here's the updated
version since I just stumbled across a new issue (case 16 below).

Below are some reasons why /usr/bin/awk on Solaris is referred to as
old, broken awk and should not be used. If on Solaris use GNU awk
(gawk), /usr/xpg4/bin/awk or New awk (nawk) instead.

If anyone has additional examples of things that are missing from and/or
broken in /usr/bin/awk feel free to post a followup but keep each point
brief.

Ed.

1) no conditions without explicit comparisons:
$ echo "foo" | /usr/xpg4/bin/awk '1{print}'
foo
$ echo "foo" | /usr/bin/awk '1==1{print}'
foo
$ echo "foo" | /usr/bin/awk '1{print}'
awk: syntax error near line 1
awk: bailing out near line 1
$ echo "foo" | /usr/bin/awk '1==1{print}'
foo

$ echo "foo" | /usr/xpg4/bin/awk '!x{print}'
foo
$ echo "foo" | /usr/bin/awk '!x{print}'
awk: syntax error near line 1
awk: bailing out near line 1
foo
$ echo "foo" | /usr/bin/awk 'x!=0{print}'
foo

2) no ternary expressions:
$ echo "foo" | /usr/xpg4/bin/awk '{print ($0=="foo") ? "yes" : "no"}'
yes
$ echo "foo" | /usr/bin/awk '{print ($0=="foo") ? "yes" : "no"}'
awk: syntax error near line 1
awk: illegal statement near line 1

3) no ARGC:
$ echo "foo" | /usr/xpg4/bin/awk '{print "<"ARGC">"}'
<1>
$ echo "foo" | /usr/bin/awk '{print "<"ARGC">"}'
<>

4) no sub()/gsub():
$ echo "foo" | /usr/xpg4/bin/awk '{print "<" sub(/o/,"X") ">"}'
<1>
$ echo "foo" | /usr/bin/awk '{print "<" sub(/o/,"X") ">"}'
awk: syntax error near line 1
awk: illegal statement near line 1

5) no -v:
$ echo "foo" | /usr/xpg4/bin/awk -v var="X" '{print "<" $0,var ">"}'
<foo X>
$ echo "foo" | /usr/bin/awk -v var="X" '{print "<" $0,var ">"}'
awk: syntax error near line 1
awk: bailing out near line 1

6) inexplicable parameter parsing (here thinks "<bar>" is arg to sprintf()):
$ echo "foo" | /usr/xpg4/bin/awk '{print sprintf("%s =",$0), "<bar>"}'
foo = <bar>
$ echo "foo" | /usr/bin/awk '{print sprintf("%s =",$0), "<bar>"}'
foo =

7) no functions:
$ echo "foo" | /usr/xpg4/bin/awk 'function bar(){print} {bar()}'
foo
$ echo "foo" | /usr/bin/awk 'function bar(){print} {bar()}'
awk: syntax error near line 1
awk: bailing out near line 1

8) no dynamic REs:
$ echo "foo" | /usr/xpg4/bin/awk 'BEGIN{re="o"} $0 ~ re {print}'
foo
$ echo "foo" | /usr/bin/awk 'BEGIN{re="o"} $0 ~ re {print}'
awk: syntax error near line 1
awk: bailing out near line 1

9) Hangs if no input and no explicit exit:
$ time /usr/xpg4/bin/awk 'BEGIN{print "begin"}'
begin

real 0m0.06s
user 0m0.01s
sys 0m0.02s
$ time /usr/bin/awk 'BEGIN{print "begin"}'
begin
^?$

10) Can't delete an array element:
$ /usr/xpg4/bin/awk 'BEGIN{ a[1]=a[2]; delete a[1]; for (i in a) print
i; exit }'
2
$ /usr/bin/awk 'BEGIN{ a[1]=a[2]; delete a[1]; for (i in a) print i;
exit }'
2
1

11) Can't test for an element being "in" an array:
$ /usr/xpg4/bin/awk 'BEGIN{ a[1]=7; if (1 in a) print a[1]; exit }'
7
$ /usr/bin/awk 'BEGIN{ a[1]=7; if (1 in a) print a[1]; exit }'
awk: syntax error near line 1
awk: illegal statement near line 1

12) No FNR variable:
$ cat file1
a
$ cat file2
b
$ /usr/xpg4/bin/awk 'NR==FNR{print}' file1 file2
a
$ /usr/bin/awk 'NR==FNR{print}' file1 file2

13) No match() function:
$ /usr/xpg4/bin/awk '{print match($0,"a")}' file1 file2
1
0
$ /usr/bin/awk '{print match($0,"a")}' file1 file2
awk: syntax error near line 1
awk: illegal statement near line 1

14) FS cannot be an RE:
$ echo "faobo" | /usr/xpg4/bin/awk '{ print $1,$2,$3 }' FS="[ab]"
f o o
$ echo "faobo" | /usr/bin/awk '{ print $1,$2,$3 }' FS="[ab]"
faobo

15) Cannot set $0:
$ /usr/xpg4/bin/awk 'BEGIN{$0="foo"; print}'
foo
$ /usr/bin/awk 'BEGIN{$0="foo"; print}'
awk: can't set $0

16) Strings can unexpectedly become numeric variables:
$ /usr/xpg4/bin/awk 'BEGIN{ c=3; print "c=" ++c; exit }'
c=4
$ /usr/bin/awk 'BEGIN{ c=3; print "c=" ++c; exit }'
03
$ /usr/xpg4/bin/awk 'BEGIN{ c=3; print "c=" ++c; print ++"c=" c; exit }'
/usr/xpg4/bin/awk: syntax error Context is:
>>> BEGIN{ c=3; print "c=" ++c; print ++"c=" <<<
$ /usr/bin/awk 'BEGIN{ c=3; print "c=" ++c; print ++"c=" c; exit }'
03
23

Posted using www.webuse.net

[Kees Nuyt]

On Wed, 04 Jan 2012 20:10:15 GMT, "Ed Morton"
<morto...@gmail.com> wrote:

>
>I had a thread on this a couple of years ago, but here's the updated
>version since I just stumbled across a new issue (case 16 below).
>
>Below are some reasons why /usr/bin/awk on Solaris is referred to as
>old, broken awk and should not be used. If on Solaris use GNU awk
>(gawk), /usr/xpg4/bin/awk or New awk (nawk) instead.
>
>If anyone has additional examples of things that are missing from and/or
>broken in /usr/bin/awk feel free to post a followup but keep each point
>brief.

Related:

http://www.shelldorado.com/articles/awkcompat.html

Best regards,
--
( Kees Nuyt
)
c[_]

[pgas]

On Jan 4, 10:10 pm, "Ed Morton" <mortons...@gmail.com> wrote:
> I had a thread on this a couple of years ago, but here's the updated
> version since I just stumbled across a new issue (case 16 below).
>
> Below are some reasons why /usr/bin/awk on Solaris is referred to as
> old, broken awk and should not be used. If on Solaris use GNU awk
> (gawk), /usr/xpg4/bin/awk or New awk (nawk) instead.
>
> If anyone has additional examples of things that are missing from and/or
> broken in /usr/bin/awk feel free to post a followup but keep each point
> brief.
>
>         Ed.

I took the liberty to copy this post here:

* http://awk.freeshell.org/oawk

if it's not ok, delete it or tell me and i'll remove it.
Thanks!