Change uses the same pattern matcher as match . If a pattern contains special characters from the pattern matcher, these characters must be preceded by a backslash '\\'. It is a good idea to put strings in single quotes if they contain special characters from the pattern matcher. This prevents the shell from treating such a string and eating up the quote characters before they are seen by change.
If the character '&' appears in the to_string , it replaces what has matched in the from_string . Multiple occurrences of '&' are possible.
Change by default creates backup files similar to ved . The old file is renamed to xxx.bak and a new file with the old name and old permissions is created. If the -nobak option is present, the old file is removed and a new file is created.
The file is treated line by line. If a pattern occurs more than once on a single line, all occurrences of that pattern are changed unless the -# option is present.
If no file names are present, change operates as filter from stdin to stdout .
-v Be verbose: Displays lines before they are changed.
-c Displays lines after they are changed.
-i Interactive prompting for each change
-# Maximum number of changes per line
-nobak Do not create a xxx.bak file with the old content.
-help Prints a short summary of the change options and exists.
-version Prints the change version number string and exists.
If no match for the from_pattern occurs in a file, it is not changed and the time stamp of that file is not affected. If change is used on several source files, this help the make program to know that only the changed files need to be recompiled.
If a file with more than name is changed, a new file is created. The new file is no more linked to the other files and the content of the other files is not changed.
See match (1) for a detailed description of allowed patterns.