From: Alejandro Colomar via Libc-alpha <libc-alpha@sourceware.org>
To: mtk.manpages@gmail.com
Cc: Alejandro Colomar <colomar.6.4.3@gmail.com>,
linux-man@vger.kernel.org, libc-alpha@sourceware.org
Subject: [PATCH v2] regex.3: Add example program
Date: Sat, 17 Oct 2020 15:27:49 +0200 [thread overview]
Message-ID: <20201017132748.150322-1-colomar.6.4.3@gmail.com> (raw)
In-Reply-To: <efc1c2c5-3cf9-e755-cab3-c19e100f210b@gmail.com>
$ gcc -Wall -Wextra -Werror -pedantic regex.c -o regex
$ ./regex.3
String = "1) John Driverhacker;
2) John Doe;
3) John Foo;
"
Matches:
#0:
offset = 25; length = 7
substring = "John Do"
#1:
offset = 38; length = 8
substring = "John Foo"
Signed-off-by: Alejandro Colomar <colomar.6.4.3@gmail.com>
---
Hi Michael,
Now it's much better :)
Cheers,
Alex
man3/regex.3 | 42 +++++++++++++++++++++++++++++++++++++++++++
1 file changed, 42 insertions(+)
diff --git a/man3/regex.3 b/man3/regex.3
index 7c5132995..72e576cc6 100644
--- a/man3/regex.3
+++ b/man3/regex.3
@@ -337,6 +337,48 @@ T} Thread safety MT-Safe
.TE
.SH CONFORMING TO
POSIX.1-2001, POSIX.1-2008.
+.SH EXAMPLES
+.EX
+#include <stdint.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <regex.h>
+
+#define ARRAY_SIZE(arr) (sizeof((arr)) / sizeof((arr)[0]))
+
+static const char *const str =
+ "1) John Driverhacker;\en2) John Doe;\en3) John Foo;\en";
+static const char *const re = "John.*o";
+
+int main(void)
+{
+ static const char *s = str;
+ regex_t regex;
+ regmatch_t pmatch[1];
+ regoff_t off, len;
+
+ if (regcomp(®ex, re, REG_NEWLINE))
+ exit(EXIT_FAILURE);
+
+ printf("String = \\"%s\\"\en", str);
+ printf("Matches:\en");
+
+ for (int i = 0; ; i++) {
+ if (regexec(®ex, s, ARRAY_SIZE(pmatch), pmatch, 0))
+ break;
+
+ off = pmatch[0].rm_so + (s \- str);
+ len = pmatch[0].rm_eo \- pmatch[0].rm_so;
+ printf("#%d:\en", i);
+ printf("offset = %jd; length = %jd\en", (intmax_t) off, (intmax_t) len);
+ printf("substring = \\"%.*s\\"\en", len, s + pmatch[0].rm_so);
+
+ s += pmatch[0].rm_eo;
+ }
+
+ exit(EXIT_SUCCESS);
+}
+.EE
.SH SEE ALSO
.BR grep (1),
.BR regex (7)
--
2.28.0
next prev parent reply other threads:[~2020-10-17 13:30 UTC|newest]
Thread overview: 5+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-10-17 13:13 [PATCH] regex.3: Add example program Alejandro Colomar via Libc-alpha
2020-10-17 13:17 ` Alejandro Colomar via Libc-alpha
2020-10-17 13:27 ` Alejandro Colomar via Libc-alpha [this message]
2020-10-17 13:37 ` [PATCH v2] " Alejandro Colomar via Libc-alpha
2020-10-17 14:35 ` Michael Kerrisk (man-pages) via Libc-alpha
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