awk - Splitting Filename delimited by period (.)

Question

I'm writting an sh file where I have var as:

c=aabbcc.DP.09-25-2012_14_17.dmp

i want to copy only initial part in another var like:

d = aabbcc

How should I trim my var?

Answer 1

If by sh you mean bash, then

d="${c%%.*}"

otherwise

d="`echo "$d"|cut -d. -f1`"

will do, perhaps.

Answer 2

perl:

D=`echo $c | perl -lne 's/([^\.]*)\..*/\1/;print'`

赛德：

D=`echo $c | sed 's/\([^\.]*\)\..*/\1/'`

awk：

D=`echo $c | awk -F. '{print $1}'`

Answer 3

expr 命令兼容任何 sh 实现，不需要管道

d=`expr $c : '\([^\.]*\)'`