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From: Sami Kerola <kerolasa@iki.fi>
To: util-linux@vger.kernel.org
Cc: kerolasa@iki.fi
Subject: [PATCH 2/3] more: make output redirection more efficient
Date: Sun,  4 Aug 2013 00:15:20 +0100	[thread overview]
Message-ID: <1375571721-30008-2-git-send-email-kerolasa@iki.fi> (raw)
In-Reply-To: <1375571721-30008-1-git-send-email-kerolasa@iki.fi>

Especially with large inputs the change improves performance
considerably.

old> time more /boot/vmlinuz >/dev/null
real    0m0.224s

new> more /boot/vmlinuz >/dev/null
real    0m0.009s

Signed-off-by: Sami Kerola <kerolasa@iki.fi>
---
 text-utils/more.c | 7 ++++---
 1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/text-utils/more.c b/text-utils/more.c
index ac35acc..598e048 100644
--- a/text-utils/more.c
+++ b/text-utils/more.c
@@ -780,10 +780,11 @@ void __attribute__((__noreturn__)) end_it(int dummy __attribute__((__unused__)))
 
 void copy_file(register FILE *f)
 {
-	register int c;
+	char buf[BUFSIZ];
+	size_t sz;
 
-	while ((c = getc(f)) != EOF)
-		putchar(c);
+	while ((sz = fread(&buf, sizeof(char), sizeof(buf), f)) > 0)
+		fwrite(&buf, sizeof(char), sz, stdout);
 }
 
 #define ringbell()	putcerr('\007')
-- 
1.8.3.4


  reply	other threads:[~2013-08-03 23:15 UTC|newest]

Thread overview: 6+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2013-08-03 23:15 [PATCH 1/3] column: use variable lenght printf field width to wprint blanks Sami Kerola
2013-08-03 23:15 ` Sami Kerola [this message]
2013-08-05  8:48   ` [PATCH 2/3] more: make output redirection more efficient Karel Zak
2013-08-03 23:15 ` [PATCH 3/3] cal: set statically defined data read-only Sami Kerola
2013-08-05  8:49   ` Karel Zak
2013-08-05  8:48 ` [PATCH 1/3] column: use variable lenght printf field width to wprint blanks Karel Zak

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