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Updated SC2126 (markdown)

Michael Diamond
2020-04-23 11:58:24 -07:00
parent df4551468a
commit 98cb2ca30e
1 changed files with 4 additions and 5 deletions
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SC2126.md

@@ -20,7 +20,7 @@ Instead of:
grep foo *.log | wc -l
```
Pipe all the file contents into `grep` (passing the files directly to `grep` causes `-c` to print each file's count separately, rather than the total):
You can pipe all the file contents into `grep` (passing the files directly to `grep` causes `-c` to print each file's count separately, rather than the total):
```sh
cat *.log | grep foo -c
@@ -30,11 +30,10 @@ cat *.log | grep foo -c
This is purely a stylistic issue. `grep` can count lines without piping to `wc`.
Note that in many cases, this number is only used to see whether there are matches (i.e. `== 0`). In these cases, it's better and more efficient to use `grep -q` and check its exit status:
Often this number is only used to see whether there are matches (i.e. `== 0`). In these cases it's clearer and more efficient to use `grep -q` and check its exit status:
```sh
if grep -q pattern file
then
if grep -q pattern file; then
echo "The file contains the pattern"
fi
```
@@ -43,4 +42,4 @@ Also note that in `foo | grep bar | wc -l`, wc will mask the exit code of grep b
### Exceptions
If you e.g. want to count characters instead of lines, and you actually care about the number and not just whether it's greater than 0, you can [[ignore]] this error.
If you find piping to `wc` is clearer in a given situation it's fine to [[ignore]] this error.