How to split string in someinteresting cases?

Shell Programming and Scripting
1

I have a variable

var=safe_alloc_TBA_details_TXXXXXX_YYYYMMDDhhmmss.csv

I want to get a part safe_alloc_TBA_details_T
If I do :

PR=`echo "$var" | awk -F'_' '{for (i=1; i<NF; i++) printf("%s_", $i)}'`

Then echo "$PR = safe_alloc_TBA_details_"
How can I cut the string so that get it safe_alloc_TBA_details_T ?

2

Like so?

echo ${var%${var#*_*_*_*_?}}
safe_alloc_TBA_details_T
3

RudiC,
I don't know amount of delimiters. It can be 4, 5 7, may be 2. I need some generic regular expression

Thanks

4

what can be assumed constant in this pattern/string?

safe_alloc_TBA_details_TXXXXXX_YYYYMMDDhhmmss.csv

will this help?

echo 'safe_alloc_TBA_details_TXXXXXX_YYYYMMDDhhmmss.csv' | sed 's/\(.*_T\)[^_][^_]*_.*csv$/\1/'