Quick reference

.

Mac: \r

Unix: \n
Windows: \r\n
vi s/,/,\r/
$CRLF = "\015\012";
perl -le'$q = "\047"; print $q' # single quote

unset PERL5LIB; unset PERL_LOCAL_LIB_ROOT; unset PERL_MB_OPT; unset PERL_MM_OPT; eval $(perl -Mlocal::lib=./local)

perl -MDevel::Cover=+ignore,.*,-select,^lib,-select,^t,-silent,on t/path/to/test.t

python -m SimpleHTTPServer 8080
python3 -m http.server 8080

warn "mojo response = ".$t->tx->res->to_string;
...->or(sub { diag("Result = ".$t->tx->res->to_string) });

use Data::Printer { class => { internals => 0, inherited => 'public' } };

my $r=\@_; $l->debug("entering ".( caller(0) )[3])." with ". sub { $l->dump(args => $r) }); # log calls to subroutines

patch -p0 < file.patch

DBIC_TRACE_PROFILE=console DBIC_TRACE=1
TEST_METHOD=foo

$Data::Dumper::Maxdepth = 1;

$DB::single = 1;

echo -ne "\033]0;"some title"\007" # set putty title

shopt -s checkwinsize; reset # fix terminal display issue

# bash strict mode
set -euo pipefail
IFS=$'\n\t'
# debug mode
set -vx

(s)printf:
printf '<%+d>', 12; # prints "<+12>"
printf '<%6s>', 12; # prints "< 12>"
printf '<%-6s>', 12; # prints "<12 >"

eval $(dircolors|sed 's/di=01;34/di=01;36/'); # light blue directories

if [ "$(id -u)" != "0" ]; then
echo "This script must be run as root"
exit 1
fi

| python -m json.tool # sorts keys
| json_pp # doesn't sort keys (perl JSON module)

Search and replace over two lines:
sed ':a;N;$!ba;s/\n second line: / second line: /g'


Bash quotes: '\'' & '"'"'

print "debug = ".Dumper({%{{$_->get_columns}}{qw/id shipment_id/}}) foreach $shipment_rs->items; # DBIC quick peek

print $result->{_column_data} # DBIC quicker peek

require Carp; Carp::cluck "got here";

telnet host port

openssl s_client -debug -connect host:port

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