perldoc -f index

index STR,SUBSTR,POSITION
index STR,SUBSTR
The index function searches for one string within another, but without the wildcard-like behavior of a full regular-expression pattern match. It returns the position of the first occurrence of SUBSTR in STR at or after POSITION. If POSITION is omitted, starts searching from the beginning of the string. The return value is based at 0 (or whatever you've set the $[ variable to--but don't do that). If the substring is not found, returns one less than the base, ordinarily "-1".

 $> perl -e "\$pos = -1;print (\$pos . ' ') 
while((\$pos = index('joe,is,at,home', ',', \$pos+1)) != -1);"
3 6 9
[download]

Edit:fixed pos init-value

regards,
tomte

Hlade's Law:

If you have a difficult task, give it to a lazy person --
they will find an easier way to do it.

++tomte for a good answer.

I'd change the example a little. The quoting style used makes this one-liner hard to read - it forces backlashes where they aren't expected. With a *nix shell, single quotes won't force you to escape the dollar signs, ie:

 $> perl -e '$pos = 0;print ($pos . " ") 
while(($pos = index("joe,is,at,home", ",", $pos+1)) != -1);'
3 6 9
[download]

$_ = q(joe,is,at,home,and,going,to,market,);
while(/\,/g){
    print pos()," ";
}
[download]

Answer:

4 7 10 15 19 25 28 35

$_ = "joe,is,at,home";
my @pos;
push @pos, pos()-1 while /,/g;
print "@pos\n";
[download]

-- Mike

--
just,my${.02}

What I really needs I have user credentials in a older system in jdoe,dept,comp and I need it in fully distiguisded to manipulate using ldap like cn=jdoe,ou=dept,o=comp.

$input_string = "jdoe,dept,comp\n";
chomp $input_string;
($cn_temp, $ou_temp, $o_temp) = split /,/ , $input_string;
print "cn=$cn_temp,ou=$ou_temp,o=$o_temp\n";
[download]

will print "cn=jdoe,ou=dept,o=comp" -- Perl has many wonderful string tools, you dont have to do it like C. =)

-Waswas