extract and display matching strings with similar pattern-CodePudding

I have an extremely long line. It contains a lot of strings with a similar patterns like below;

t[0-4]_vmdk_[a-z]_anything

t followed by a single digit with possible 0-4, and them '_vmdk_', and any long string with possible [a-z], then finally "_" in the end. The rest could be anything.

Ex:

asdfasfsa/_asdf**t2_vmdk_abc_**badfad**t3_vmdk_xyz_**asdfasdf**t1_vmdk_efg_**asbafdfb....

Please help me to display all such strings. Thank you!

CodePudding user response：

The simplest is probably with grep. If the input string comes from the standard output of another command (e.g. echo):

$ str='asdfasfsa/_asdf**t2_vmdk_abc_**badfad**t3_vmdk_xyz_**asdfasdf**t1_vmdk_efg_**asbafdfb....'
$ echo "$str" | grep -o 't[0-4]_vmdk_[a-z]*'
t2_vmdk_abc
t3_vmdk_xyz
t1_vmdk_efg

Explanation: the -o option prints "only the matched (non-empty) parts of a matching line".

If the input strings are stored in a file:

$ grep -o 't[0-4]_vmdk_[a-z]*' file.txt
t2_vmdk_abc
t3_vmdk_xyz
t1_vmdk_efg