git/list[1] front-page[2] threads[3] people[4] search[5] about
 

[PATCH] Remove useless uses of cat, and replace with filename arguments or redirection

From
Josh Triplett <josh@freedesktop.org>
Date
Jun 6, 2007, 01:34 UTC
Message-ID
<46660F43.4060402@freedesktop.org>
Replace all uses of cat that do nothing other than read a single file.
Signed-off-by: Josh Triplett <josh@freedesktop.org>
---
 git-commit.sh        |    2 +-
 git-filter-branch.sh |    4 ++--
 git-ls-remote.sh     |    2 +-
 git-quiltimport.sh   |    4 ++--
 git-verify-tag.sh    |    3 +--
 5 files changed, 7 insertions(+), 8 deletions(-)
diff --git a/git-commit.sh b/git-commit.sh
index e8b60f7..06b6cd7 100755
--- a/git-commit.sh
+++ b/git-commit.sh
@@ -617,7 +617,7 @@ then
 		tree=$(GIT_INDEX_FILE="$TMP_INDEX" git-write-tree) &&
 		rm -f "$TMP_INDEX"
 	fi &&
-	commit=$(cat "$GIT_DIR"/COMMIT_MSG | git-commit-tree $tree $PARENTS) &&
+	commit=$(git-commit-tree $tree $PARENTS < "$GIT_DIR"/COMMIT_MSG) &&
 	rlogm=$(sed -e 1q "$GIT_DIR"/COMMIT_MSG) &&
 	git-update-ref -m "$GIT_REFLOG_ACTION: $rlogm" HEAD $commit "$current" &&
 	rm -f -- "$GIT_DIR/MERGE_HEAD" "$GIT_DIR/MERGE_MSG" &&
diff --git a/git-filter-branch.sh b/git-filter-branch.sh
index 0c8a7df..bfac6f2 100644
--- a/git-filter-branch.sh
+++ b/git-filter-branch.sh
@@ -333,7 +333,7 @@ for commit in $unchanged; do
 done
 
 git-rev-list --reverse --topo-order $srcbranch --not $unchanged >../revs
-commits=$(cat ../revs | wc -l | tr -d " ")
+commits=$(wc -l ../revs | tr -d " ")
 
 test $commits -eq 0 && die "Found nothing to rewrite"
 
@@ -386,7 +386,7 @@ while read commit; do
 done <../revs
 
 git-update-ref refs/heads/"$dstbranch" $(head -n 1 ../map/$(tail -n 1 ../revs))
-if [ "$(cat ../map/$(tail -n 1 ../revs) | wc -l)" -gt 1 ]; then
+if [ "$(wc -l ../map/$(tail -n 1 ../revs))" -gt 1 ]; then
 	echo "WARNING: Your commit filter caused the head commit to expand to several rewritten commits. Only the first such commit was recorded as the current $dstbranch head but you will need to resolve the situation now (probably by manually merging the other commits). These are all the commits:" >&2
 	sed 's/^/	/' ../map/$(tail -n 1 ../revs) >&2
 	ret=1
diff --git a/git-ls-remote.sh b/git-ls-remote.sh
index a6ed99a..f5b2e77 100755
--- a/git-ls-remote.sh
+++ b/git-ls-remote.sh
@@ -82,7 +82,7 @@ rsync://* )
 	(cd $tmpdir && find refs -type f) |
 	while read path
 	do
-		cat "$tmpdir/$path" | tr -d '\012'
+		tr -d '\012' < "$tmpdir/$path"
 		echo "	$path"
 	done &&
 	rm -fr $tmpdir
diff --git a/git-quiltimport.sh b/git-quiltimport.sh
index a7a6757..bd540cd 100755
--- a/git-quiltimport.sh
+++ b/git-quiltimport.sh
@@ -70,9 +70,9 @@ tmp_info="$tmp_dir/info"
 commit=$(git-rev-parse HEAD)
 
 mkdir $tmp_dir || exit 2
-for patch_name in $(cat "$QUILT_PATCHES/series" | grep -v '^#'); do
+for patch_name in $(grep -v '^#' "$QUILT_PATCHES/series"); do
 	echo $patch_name
-	(cat $QUILT_PATCHES/$patch_name | git-mailinfo "$tmp_msg" "$tmp_patch" > "$tmp_info") || exit 3
+	git-mailinfo "$tmp_msg" "$tmp_patch" < "$QUILT_PATCHES/$patch_name" > "$tmp_info" || exit 3
 	test -s .dotest/patch || {
 		echo "Patch is empty.  Was it split wrong?"
 		exit 1
diff --git a/git-verify-tag.sh b/git-verify-tag.sh
index 8db7dd0..11ce947 100755
--- a/git-verify-tag.sh
+++ b/git-verify-tag.sh
@@ -38,8 +38,7 @@ trap 'rm -f "$GIT_DIR/.tmp-vtag"' 0
 
 git-cat-file tag "$1" >"$GIT_DIR/.tmp-vtag" || exit 1
 
-cat "$GIT_DIR/.tmp-vtag" |
-sed '/-----BEGIN PGP/Q' |
+sed '/-----BEGIN PGP/Q' "$GIT_DIR/.tmp-vtag" |
 gpg --verify "$GIT_DIR/.tmp-vtag" - || exit 1
 rm -f "$GIT_DIR/.tmp-vtag"
 
-- 
1.5.2.1
Next: Stephen Rothwell
Message 1 of 6 in “Remove useless uses of cat, and replace with filename arguments or redirection”
  1. Remove useless uses of cat, and replace with filename arguments or redirectionJosh Triplett, Jun 6, 2007
  2. Stephen RothwellJun 6, 2007
  3. Michael PooleJun 6, 2007
  4. Martin LanghoffJun 6, 2007
  5. Stephen RothwellJun 6, 2007
  6. Martin LanghoffJun 6, 2007

Read the whole thread, see it on lore, or plain text.

$ cat FOOTERMessages come from the public archive at lore.kernel.org/git, fetched every hour. The front page is chosen and written each morning by an AI editor and can be wrong; the threads themselves are the record. About and API. For agents: an MCP server at https://gitlist.dev/mcp, and any thread, story or person page as Markdown by adding .md to its URL (or sending Accept: text/markdown). Details in /llms.txt.