use @@PERL@@ in built scripts

Several of the built shell commands invoke a bare "perl" to
perform some one-liners. This will use the first perl in the
PATH rather than the one specified by the user's SHELL_PATH.
We are not asking these perl invocations to do anything
exotic, so typically any old system perl will do; however,
in some cases the system perl may have unexpected behavior
(e.g., by handling line endings differently). We should err
on the side of using the perl the user pointed us to.

The downside of this is that on systems with a sane perl
setup, we no longer find the perl at runtime, but instead
point to a static perl (like /usr/bin/perl). That means we
will not handle somebody moving perl without rebuilding git,
whereas before we tracked it just fine. This is probably not
a big deal, though, as the built perl scripts already
suffered from this.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

4 files changed, 5 insertions, 5 deletions

diff --git a/git-am.sh b/git-am.sh
index 202130f888..46e83569aa 100755
--- a/git-am.sh
+++ b/git-am.sh
@@ -302,7 +302,7 @@ split_patches () {
 			# not starting with Author, From or Date is the
 			# subject, and the body starts with the next nonempty
 			# line not starting with Author, From or Date
-			perl -ne 'BEGIN { $subject = 0 }
+			@@PERL@@ -ne 'BEGIN { $subject = 0 }
 				if ($subject > 1) { print ; }
 				elsif (/^\s+$/) { next ; }
 				elsif (/^Author:/) { s/Author/From/ ; print ;}
@@ -334,7 +334,7 @@ split_patches () {
 			# Since we cannot guarantee that the commit message is in
 			# git-friendly format, we put no Subject: line and just consume
 			# all of the message as the body
-			LANG=C LC_ALL=C perl -M'POSIX qw(strftime)' -ne 'BEGIN { $subject = 0 }
+			LANG=C LC_ALL=C @@PERL@@ -M'POSIX qw(strftime)' -ne 'BEGIN { $subject = 0 }
 				if ($subject) { print ; }
 				elsif (/^\# User /) { s/\# User/From:/ ; print ; }
 				elsif (/^\# Date /) {
diff --git a/git-instaweb.sh b/git-instaweb.sh
index 01a1b05e6b..e93a238675 100755
--- a/git-instaweb.sh
+++ b/git-instaweb.sh
@@ -581,7 +581,7 @@ EOF
 
 gitweb_conf() {
 	cat > "$fqgitdir/gitweb/gitweb_config.perl" <<EOF
-#!/usr/bin/perl
+#!@@PERL@@
 our \$projectroot = "$(dirname "$fqgitdir")";
 our \$git_temp = "$fqgitdir/gitweb/tmp";
 our \$projects_list = \$projectroot;
diff --git a/git-request-pull.sh b/git-request-pull.sh
index d566015975..46be6a29ae 100755
--- a/git-request-pull.sh
+++ b/git-request-pull.sh
@@ -96,7 +96,7 @@ find_matching_ref='
 	}
 '
 
-ref=$(git ls-remote "$url" | perl -e "$find_matching_ref" "$head" "$headrev" "$tag_name")
+ref=$(git ls-remote "$url" | @@PERL@@ -e "$find_matching_ref" "$head" "$headrev" "$tag_name")
 
 url=$(git ls-remote --get-url "$url")
 
diff --git a/git-submodule.sh b/git-submodule.sh
index b3108b8ea9..4cf94d1056 100755
--- a/git-submodule.sh
+++ b/git-submodule.sh
@@ -115,7 +115,7 @@ module_list()
 		git ls-files --error-unmatch --stage -- "$@" ||
 		echo "unmatched pathspec exists"
 	) |
-	perl -e '
+	@@PERL@@ -e '
 	my %unmerged = ();
 	my ($null_sha1) = ("0" x 40);
 	my @out = ();