Shell Programming and Scripting

MYNUMBERD000000-BAN CHUE INSNTS       **    N+
MYAREDSDD000000+BAN CHUE INSNTS       **    N+
MYDERFFFSD00000-GIR PENT - ACH            **    N+
MYDDDDDAY000000+GIR PENT - ACH            **    N+

MYNUMBERD000000-TEST**    N+
MYAREDSDD000000+TEST**    N+
MYDERFFFSD00000-TEST**    N+
MYDDDDDAY000000+TEST**    N+

awk '{gsub(/-.+\*\*/,"-TEST**");gsub(/\+.+\*\*/,"+TEST**")}1' file
MYNUMBERD000000-TEST**    N+
MYAREDSDD000000+TEST**    N+
MYDERFFFSD00000-TEST**    N+
MYDDDDDAY000000+TEST**    N+

awk '{gsub(/-.+\*\*/,"-TEST**");gsub(/\+.+\*\*/,"+TEST**")}1' file.txt
awk: syntax error near line 1
awk: illegal statement near line 1
awk: syntax error near line 1
awk: illegal statement near line 1
awk: syntax error near line 1
awk: bailing out near line 1

sed

fixed column numbers, say colomn 21-40 to be replaced with some string(TEST)

sed 's/\([+-]\).*\(\*\*\)/\1TEST\2/' input_file

awk '{val=substr($0,21,19);gsub(val,"TEST",$0)}1' input_file