diffutils: patch Quoting Style
10.11.3 ‘patch’ Quoting Style
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When ‘patch’ outputs a file name in a diagnostic message, it can format
the name in any of several ways. This can be useful to output file
names unambiguously, even if they contain punctuation or special
characters like newlines. The ‘--quoting-style=WORD’ option controls
how names are output. The WORD should be one of the following:
‘literal’
Output names as-is.
‘shell’
Quote names for the shell if they contain shell metacharacters or
would cause ambiguous output.
‘shell-always’
Quote names for the shell, even if they would normally not require
quoting.
‘c’
Quote names as for a C language string.
‘escape’
Quote as with ‘c’ except omit the surrounding double-quote
characters.
You can specify the default value of the ‘--quoting-style’ option
with the environment variable ‘QUOTING_STYLE’. If that environment
variable is not set, the default value is ‘shell’, but this default may
change in a future version of ‘patch’.