grep: tighten -i doc

* doc/grep.in.1:
* doc/grep.texi (Matching Control):
* src/grep.c (usage):
Make it clearer that -i affects patterns and data, but not
file names (Bug#37604).

1 files changed, 1 insertions, 1 deletions

diff --git a/src/grep.c b/src/grep.c
index ef6abb84..4b6b4659 100644
--- a/src/grep.c
+++ b/src/grep.c
@@ -1926,7 +1926,7 @@ Pattern selection and interpretation:\n"), getprogname ());
       printf (_("\
   -e, --regexp=PATTERNS     use PATTERNS for matching\n\
   -f, --file=FILE           take PATTERNS from FILE\n\
-  -i, --ignore-case         ignore case distinctions\n\
+  -i, --ignore-case         ignore case distinctions in patterns and data\n\
   -w, --word-regexp         match only whole words\n\
   -x, --line-regexp         match only whole lines\n\
   -z, --null-data           a data line ends in 0 byte, not newline\n"));