UNIX for Dummies Questions & Answers

Z
A
T
W
Y
B
S
X

X
Y
Z
A
B
S
T
W

awk -v S="X" '
        BEGIN {
                n = split( "A B C D E F G H I J K L M N O P Q R S T U V W X Y Z", A )
                for ( i = 1; i <= n; i++ )
                {
                        if ( A[i] == S )
                                s_idx = i
                }
        }
        {
                R[$1]
                next
        }
        END {
                if ( s_idx > 1 )
                {
                        for ( j = s_idx; j <= n; j++ )
                        {
                                if ( A[j] in R )
                                        print A[j]
                        }
                        for ( k = 1; k < s_idx; k++ )
                        {
                                if ( A[k] in R )
                                        print A[k]
                        }
                }
                else
                {
                        for ( j = 1; j <= n; j++ )
                        {
                                if ( A[j] in R )
                                        print A[j]
                        }
                }
        }
' filename

#!/usr/bin/env bash

# @(#) s1	Demonstrate alternate collating sequence, msort.
# For msort, see your local repository or,
# http://www.billposer.org/Software/msort.html
# Verified: Wed Oct 21 11:02:51 CDT 2015

# Utility functions: print-as-echo, print-line-with-visual-space, debug.
# export PATH="/usr/local/bin:/usr/bin:/bin"
LC_ALL=C ; LANG=C ; export LC_ALL LANG
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 msort column

FILE=${1-data1}

pl " Input data file $FILE:"
cat $FILE

pl " Sort order file (columnized):"
column custom-1.txt

pl " Results:"
msort -q -j -l -n 1,1 -s "custom-1.txt" $FILE

exit 0

$ ./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 5.0.8 (lenny, workstation) 
bash GNU bash 3.2.39
msort 8.44
column - ( /usr/bin/column, 2007-11-20 )

-----
 Input data file data1:
Z
A
T
W
Y
B
S
X

-----
 Sort order file (columnized):
X	A	D	G	J	M	P	S	V
Y	B	E	H	K	N	Q	T	W
Z	C	F	I	L	O	R	U

-----
 Results:
X
Y
Z
A
B
S
T
W

sort file |  sed -n '/X/,${p;d}; wTMP' | cat - TMP && rm TMP
X
Y
Z
A
B
S
T
W

sort file | sed -n '
${p;x;}
/X/,${p;d;}
1h;1!H
'