Tôi cần trích xuất các chuỗi văn bản từ một tệp duy nhất chứa một dòng văn bản rất dài không có dấu phân cách. Sử dụng dòng mẫu dưới đây, đây là những sự thật được biết đến sau đây:
??????? A1XXXXXXXXXX ??????? B1XXXX ??????? A1XXXXXXXXXX ????????
1. It contains 38 fixed width record types 2. The record marker is a 7 alphanumeric character followed by, for example, ‘A1’. 3. Each record type has varying widths, for example, A1 record type will have 10 characters following it, if B1 then 4, and if C1 then 7. 4. The record types aren’t clumped together and can be in any order. As in the example, its A1,B1,A1,C1 5. The example above has 4 records and each record type needs to go to separate files. In this case 38 of them.
6. The record identifier, e.g. ????????A1, can appear in the body of the record so cannot use grep. 7. With the last point in mind, I was proposing 3 solutions but not sure on how to script this and of course would greatly appreciate some help. a. Traverse through the file from the beginning and sequentially strip out the record to the appropriate output file. For example, strip out first record type A1 to A1file which I know is 10 characters long then re-interrogate the file which will then have B1 which I know is 4 chars long, strip this out to B1file etc.. <<< this seems painful >> b. Traverse through the file and append some obscure character to each record marker within the same file. Much like above but not strip out. I understand it still will use the same logic but seems more elegant c. I did think of simply using the proposed grep -oE solution but then re-interrogate the output files to see if any of the 38 record markers exist anywhere other than at the beginning. But this might not always work.