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How to search and lossless replace strings using sed?

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# 1  
Old 12-23-2018
How to search and lossless replace strings using sed?
Hello,


I would like to replace all occurencies of long data types by others (coresponding int) using 'sed' in the extensive source code of a software package written for 32 bit CPUs.
I must use regular expressions to avoid wrong replacements like

Code:
s/unsigned[[:blank:]]+long[^_1-9A-Za-z]/ulong/g

Leaving out the regular expression suffix will also replace variable names starting with 'int' and/or 'long'.

The problem with this is that the detected suffix "[^_1-9A-Za-z]" is also replaced (by an empty string), which destroys the source code.

Is it possible to append/use the detected suffix lossless again using 'sed'?



Thanks in advance,
Michael
# 2  
Old 12-23-2018
Welcome to the forum.


That is a brilliant application for a "back reference". man regex:
Quote:
Finally, there is one new type of atom, a back reference: '\' followed by a nonzero decimal digit d matches the same sequence of characters matched by the dth parenthesized subexpression (numbering subexpressions by the positions of their opening parentheses, left to right)
,


Try

Code:
s/unsigned[[:blank:]]+long([^_1-9A-Za-z])/ulong\1/g

Your original code seems to use EREs (extended regexes). Should that be wrong, escape the parantheses.
# 3  
Old 12-23-2018
it's hard to imagine that after "unsigned long" there is no whitespace
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