Add {str,mem}[r][case]eqlen

Signed-off-by: Mattias Andrée <maandree@kth.se>

61 files changed, 1108 insertions, 59 deletions

diff --git a/Makefile b/Makefile
index 09d3d15..78b071a 100644
--- a/Makefile
+++ b/Makefile
@@ -43,12 +43,12 @@ OBJ =\
 	difftimeval.o\
 	doubletotimespec.o\
 	doubletotimeval.o\
-	enaligned_memdup.o\
 	enaligned_allocz.o\
-	enposix_memalignz.o\
+	enaligned_memdup.o\
 	encalloc.o\
 	enmalloc.o\
 	enmemdup.o\
+	enposix_memalignz.o\
 	enrealloc.o\
 	enstrdup.o\
 	enstrndup.o\
@@ -59,13 +59,17 @@ OBJ =\
 	envputenvf.o\
 	envreallocn.o\
 	isutf8.o\
+	memcaseeqlen.o\
 	memdup.o\
 	memelem.o\
 	memends.o\
+	memeqlen.o\
 	memmem.o\
 	mempsetelem.o\
+	memrcaseeqlen.o\
 	memrchr.o\
 	memrelem.o\
+	memreqlen.o\
 	memrmem.o\
 	memstarts.o\
 	minimise_number_string.o\
@@ -77,9 +81,11 @@ OBJ =\
 	strcasechr.o\
 	strcasechrnul.o\
 	strcaseends.o\
+	strcaseeqlen.o\
 	strcasestr.o\
 	strchrnul.o\
 	strends.o\
+	streqlen.o\
 	strncasestr.o\
 	strndup.o\
 	strnstr.o\
diff --git a/libsimple.c b/libsimple.c
index a874258..aecd0a3 100644
--- a/libsimple.c
+++ b/libsimple.c
@@ -97,7 +97,7 @@ main(void)
 	const char *cs;
 	char buf[1024], *s;
 	int intarray[10], fds[2], oldfd;
-	size_t i, n;
+	size_t i, j, n;
 
 	assert(libsimple_default_failure_exit == 1);
 
@@ -1226,6 +1226,46 @@ main(void)
 	fprintf(stderr, "warning: libsimple_vasprintfa missing\n");
 #endif
 
+	{
+		char a[] = "abcdefgh", b[] = "abcdefgh";
+		assert(libsimple_strreqlen("", "") == 0);
+		assert(libsimple_strreqlen("x", "") == 0);
+		assert(libsimple_strreqlen("x", "y") == 0);
+		assert(libsimple_strreqlen("", "y") == 0);
+		for (i = 0; i <= 8; i++) {
+			for (j = 0; j <= 8; j++) {
+				assert(libsimple_strreqlen(&a[i], &b[j]) == 8 - (i > j ? i : j));
+				a[i] = b[j] = '\0';
+				assert(libsimple_strreqlen(a, b) == (i == j ? i : 0));
+				a[i] = "abcdefgh"[i];
+				b[j] = "abcdefgh"[j];
+			}
+		}
+		assert(libsimple_strreqlen("abc", "ABC") == 0);
+		assert(libsimple_strreqlen("123", "123") == 3);
+	}
+
+	{
+		char a[] = "abcdefgh", b[] = "ABCDEFGH";
+		assert(libsimple_strrcaseeqlen("", "") == 0);
+		assert(libsimple_strrcaseeqlen("x", "") == 0);
+		assert(libsimple_strrcaseeqlen("x", "y") == 0);
+		assert(libsimple_strrcaseeqlen("", "y") == 0);
+		for (i = 0; i <= 8; i++) {
+			for (j = 0; j <= 8; j++) {
+				assert(libsimple_strrcaseeqlen(&a[i], &b[j]) == 8 - (i > j ? i : j));
+				assert(libsimple_strrcaseeqlen(&b[i], &a[j]) == 8 - (i > j ? i : j));
+				a[i] = b[j] = '\0';
+				assert(libsimple_strrcaseeqlen(a, b) == (i == j ? i : 0));
+				assert(libsimple_strrcaseeqlen(b, a) == (i == j ? i : 0));
+				a[i] = "abcdefgh"[i];
+				b[j] = "ABCDEFGH"[j];
+			}
+		}
+		assert(libsimple_strrcaseeqlen("abc", "abc") == 3);
+		assert(libsimple_strrcaseeqlen("123", "123") == 3);
+	}
+
 	if (!have_custom_malloc()) {
 		stderr_real = 1;
 		fprintf(stderr, "\nSome tests have not been ran because malloc(3) was not "
diff --git a/libsimple/mem.h b/libsimple/mem.h
index 6782c90..3092ddc 100644
--- a/libsimple/mem.h
+++ b/libsimple/mem.h
@@ -1,8 +1,21 @@
 /* See LICENSE file for copyright and license details. */
 
 
+/* TODO memcasechr */
+/* TODO rawmemcasechr */
+/* TODO memrcasechr */
+/* TODO rawmemrcasechr */
+/* TODO memcasemem */
+/* TODO memrcasemem */
+/* TODO memcasestarts */
+/* TODO memcaseends */
+/* TODO memcasecmp */
+/* TODO memcaseeq */
+
+
 /**
- * Finds the first occurence of a byte value in an array of bytes
+ * Finds the first occurence of a byte value in an array of bytes,
+ * the comparison is case-sensitive
  * 
  * This function is optimised for instances where it is already
  * known that there is at least one occurence; if is no occurence
@@ -22,7 +35,8 @@ void *libsimple_rawmemchr(const void *, int);
 
 
 /**
- * Finds the last occurence of a byte value in an array of bytes
+ * Finds the last occurence of a byte value in an array of bytes,
+ * the comparison is case-sensitive
  * 
  * @param   s  The array of bytes to search
  * @param   c  The byte value to search for
@@ -39,7 +53,8 @@ void *libsimple_memrchr(const void *, int, size_t);
 
 
 /**
- * Finds the last occurence of a byte value in an array of bytes
+ * Finds the last occurence of a byte value in an array of bytes,
+ * the comparison is case-sensitive
  * 
  * This function is optimised for instances where it is already
  * known that there is at least one occurence; if is no occurence
@@ -60,7 +75,7 @@ void *libsimple_rawmemrchr(const void *, int, size_t);
 
 
 /**
- * Finds the first substring in an array of bytes
+ * Finds the first substring in an array of bytes, the comparison is case-sensitive
  * 
  * @param   haystack   The array of bytes to search
  * @param   nhaystack  The length of `haystack`
@@ -78,7 +93,7 @@ void *libsimple_memmem(const void *, size_t, const void *, size_t);
 
 
 /**
- * Finds the last substring in an array of bytes
+ * Finds the last substring in an array of bytes, the comparison is case-sensitive
  * 
  * @param   haystack   The array of bytes to search
  * @param   nhaystack  The length of `haystack`
@@ -96,7 +111,7 @@ void *libsimple_memrmem(const void *, size_t, const void *, size_t);
 
 
 /**
- * Finds the first element in an array
+ * Finds the first element in an array, the comparison is case-sensitive
  * 
  * @param   haystack   The array of bytes to search
  * @param   nhaystack  The length of `haystack`, divided by `needle`
@@ -115,7 +130,7 @@ void *libsimple_memelem(const void *, size_t, const void *, size_t);
 
 
 /**
- * Finds the last element in an array
+ * Finds the last element in an array, the comparison is case-sensitive
  * 
  * @param   haystack   The array of bytes to search
  * @param   nhaystack  The length of `haystack`, divided by `needle`
@@ -134,7 +149,7 @@ void *libsimple_memrelem(const void *, size_t, const void *, size_t);
 
 
 /**
- * Checks the beginning of an array of bytes
+ * Checks the beginning of an array of bytes, the comparison is case-sensitive
  * 
  * @param   s  The array of bytes to check
  * @param   n  The length of `s`
@@ -150,7 +165,7 @@ int libsimple_memstarts(const void *, size_t, const void *, size_t);
 
 
 /**
- * Checks the end of an array of bytes
+ * Checks the end of an array of bytes, the comparison is case-sensitive
  * 
  * @param   s  The array of bytes to check
  * @param   n  The length of `s`
@@ -166,7 +181,7 @@ int libsimple_memends(const void *, size_t, const void *, size_t);
 
 
 /**
- * Checks two arrays of bytes for equality
+ * Checks two arrays of bytes for equality, the comparison is case-sensitive
  * 
  * @param   a  One of the arrays of bytes
  * @param   b  The other arrays of bytes
@@ -222,9 +237,10 @@ static inline void *libsimple_mempset(void *__s, int __c, size_t __n)
  * @param   nitems  The number of copies to fill `buf` with
  * @return          `&buf[nelems * size]`
  */
+_LIBSIMPLE_GCC_ONLY(__attribute__((__warn_unused_result__)))
 void *libsimple_mempsetelem(void *__buf, const void *__item, size_t __size, size_t __nitems);
-#ifndef libsimple_mempsetelem
-# define libsimple_mempsetelem libsimple_mempsetelem
+#ifndef mempsetelem
+# define mempsetelem libsimple_mempsetelem
 #endif
 
 
@@ -237,8 +253,77 @@ void *libsimple_mempsetelem(void *__buf, const void *__item, size_t __size, size
  * @param   nitems  The number of copies to fill `buf` with
  * @return          `buf`
  */
+_LIBSIMPLE_GCC_ONLY(__attribute__((__warn_unused_result__)))
 static inline void *libsimple_memsetelem(void *__buf, const void *__item, size_t __size, size_t __nitems)
 { return libsimple_mempsetelem(__buf, __item, __size, __nitems), __buf; }
-#ifndef libsimple_memsetelem
-# define libsimple_memsetelem libsimple_memsetelem
+#ifndef memsetelem
+# define memsetelem libsimple_memsetelem
+#endif
+
+
+/**
+ * Compares the beginning of two memory segments, the comparison is case-sensitive
+ * 
+ * @param   a  One of the arrays
+ * @param   n  The length of `a`
+ * @param   b  The other array
+ * @param   m  The length of `b`
+ * @return     The number of bytes `a` and `b` have
+ *             in common in their beginnings
+ */
+_LIBSIMPLE_GCC_ONLY(__attribute__((__pure__, __warn_unused_result__)))
+size_t libsimple_memeqlen(const void *, size_t, const void *, size_t);
+#ifndef memeqlen
+# define memeqlen libsimple_memeqlen
+#endif
+
+
+/**
+ * Compares the beginning of two memory segments, the comparison is case-insensitive
+ * 
+ * @param   a  One of the arrays
+ * @param   n  The length of `a`
+ * @param   b  The other array
+ * @param   m  The length of `b`
+ * @return     The number of bytes `a` and `b` have
+ *             in common in their beginnings
+ */
+_LIBSIMPLE_GCC_ONLY(__attribute__((__pure__, __warn_unused_result__)))
+size_t libsimple_memcaseeqlen(const void *, size_t, const void *, size_t);
+#ifndef memcaseeqlen
+# define memcaseeqlen libsimple_memcaseeqlen
+#endif
+
+
+/**
+ * Compares the end of two memory segments, the comparison is case-sensitive
+ * 
+ * @param   a  One of the arrays
+ * @param   n  The length of `a`
+ * @param   b  The other array
+ * @param   m  The length of `b`
+ * @return     The number of bytes `a` and `b` have
+ *             in common in their ends
+ */
+_LIBSIMPLE_GCC_ONLY(__attribute__((__pure__, __warn_unused_result__)))
+size_t libsimple_memreqlen(const void *, size_t, const void *, size_t);
+#ifndef memreqlen
+# define memreqlen libsimple_memreqlen
+#endif
+
+
+/**
+ * Compares the end of two memory segments, the comparison is case-insensitive
+ * 
+ * @param   a  One of the arrays
+ * @param   n  The length of `a`
+ * @param   b  The other array
+ * @param   m  The length of `b`
+ * @return     The number of bytes `a` and `b` have
+ *             in common in their ends
+ */
+_LIBSIMPLE_GCC_ONLY(__attribute__((__pure__, __warn_unused_result__)))
+size_t libsimple_memrcaseeqlen(const void *, size_t, const void *, size_t);
+#ifndef memrcaseeqlen
+# define memrcaseeqlen libsimple_memrcaseeqlen
 #endif
diff --git a/libsimple/str.h b/libsimple/str.h
index c046fbc..522062e 100644
--- a/libsimple/str.h
+++ b/libsimple/str.h
@@ -1,12 +1,6 @@
 /* See LICENSE file for copyright and license details. */
 
 
-/* TODO streqlen */
-/* TODO strcaseeqlen */
-/* TODO strreqlen */
-/* TODO strrcaseeqlen */
-
-
 /**
  * Scans for a character in a string, the scan is case-sensitive
  * 
@@ -104,7 +98,7 @@ int libsimple_strstarts(const char *, const char *);
  */
 _LIBSIMPLE_GCC_ONLY(__attribute__((__pure__, __nonnull__, __warn_unused_result__)))
 static inline int libsimple_strcasestarts(const char *__s, const char *__t)
-{ return !strncasecmp(__s, __t, strlen(__t)); }
+{ return !strncasecmp(__s, __t, (strlen)(__t)); }
 #ifndef strcasestarts
 # define strcasestarts libsimple_strcasestarts
 #endif
@@ -284,3 +278,65 @@ static inline int libsimple_strcaseeqnul(const char *__a, const char *__b)
 #ifndef strcaseeqnul
 # define strcaseeqnul libsimple_strcaseeqnul
 #endif
+
+
+/**
+ * Compares the beginning of two strings, the comparison is case-sensitive
+ * 
+ * @param   a  One of the strings
+ * @param   b  The other string
+ * @return     The number of bytes `a` and `b` have
+ *             in common in their beginnings
+ */
+_LIBSIMPLE_GCC_ONLY(__attribute__((__pure__, __nonnull__, __warn_unused_result__)))
+size_t libsimple_streqlen(const char *, const char *);
+#ifndef streqlen
+# define streqlen libsimple_streqlen
+#endif
+
+
+/**
+ * Compares the beginning of two strings, the comparison is case-insensitive
+ * 
+ * @param   a  One of the strings
+ * @param   b  The other string
+ * @return     The number of bytes `a` and `b` have
+ *             in common in their beginnings
+ */
+_LIBSIMPLE_GCC_ONLY(__attribute__((__pure__, __nonnull__, __warn_unused_result__)))
+size_t libsimple_strcaseeqlen(const char *, const char *);
+#ifndef strcaseeqlen
+# define strcaseeqlen libsimple_strcaseeqlen
+#endif
+
+
+/**
+ * Compares the end of two strings, the comparison is case-sensitive
+ * 
+ * @param   a  One of the strings
+ * @param   b  The other string
+ * @return     The number of bytes `a` and `b` have
+ *             in common in their ends
+ */
+_LIBSIMPLE_GCC_ONLY(__attribute__((__pure__, __nonnull__, __warn_unused_result__)))
+static inline size_t libsimple_strreqlen(const char *__a, const char *__b)
+{ return libsimple_memreqlen(__a, (strlen)(__a), __b, (strlen)(__b)); }
+#ifndef strreqlen
+# define strreqlen libsimple_strreqlen
+#endif
+
+
+/**
+ * Compares the end of two strings, the comparison is case-insensitive
+ * 
+ * @param   a  One of the strings
+ * @param   b  The other string
+ * @return     The number of bytes `a` and `b` have
+ *             in common in their ends
+ */
+_LIBSIMPLE_GCC_ONLY(__attribute__((__pure__, __nonnull__, __warn_unused_result__)))
+static inline size_t libsimple_strrcaseeqlen(const char *__a, const char *__b)
+{ return libsimple_memrcaseeqlen(__a, (strlen)(__a), __b, (strlen)(__b)); }
+#ifndef strrcaseeqlen
+# define strrcaseeqlen libsimple_strrcaseeqlen
+#endif
diff --git a/man/libsimple_getenv_e.3 b/man/libsimple_getenv_e.3
index 27fba39..7e3a3ca 100644
--- a/man/libsimple_getenv_e.3
+++ b/man/libsimple_getenv_e.3
@@ -11,7 +11,7 @@ static inline const char *libsimple_getenv_e(const char *\fIname\fP);
 # define getenv_e libsimple_getenv_e
 #endif
 .fi
-
+.PP
 Link with
 .IR \-lsimple .
 .SH DESCRIPTION
diff --git a/man/libsimple_getenv_ne.3 b/man/libsimple_getenv_ne.3
index a0eca77..55b592e 100644
--- a/man/libsimple_getenv_ne.3
+++ b/man/libsimple_getenv_ne.3
@@ -11,7 +11,7 @@ static inline char *libsimple_getenv_ne(const char *\fIname\fP);
 # define getenv_ne libsimple_getenv_ne
 #endif
 .fi
-
+.PP
 Link with
 .IR \-lsimple .
 .SH DESCRIPTION
diff --git a/man/libsimple_memcaseeqlen.3 b/man/libsimple_memcaseeqlen.3
new file mode 100644
index 0000000..8cad3ca
--- /dev/null
+++ b/man/libsimple_memcaseeqlen.3
@@ -0,0 +1,75 @@
+.TH LIBSIMPLE_MEMCASEEQLEN 3 2018-10-21 libsimple
+.SH NAME
+libsimple_memcaseeqlen \- check initial commonality
+.SH SYNOPSIS
+.nf
+#include <libsimple.h>
+
+size_t libsimple_memcaseeqlen(const void *\fIa\fP, size_t \fIn\fP, const void *\fIb\fP, size_t \fIm\fP);
+
+#ifndef memcaseeqlen
+# define memcaseeqlen libsimple_memcaseeqlen
+#endif
+.fi
+.PP
+Link with
+.IR \-lsimple .
+.SH DESCRIPTION
+The
+.BR libsimple_memcaseeqlen ()
+function scans the number of bytes the byte array
+.IR a ,
+with size
+.IR n ,
+have in common the byte array
+.IR b ,
+with size
+.IR m ,
+at their beginnings.
+.PP
+The comparison is case-insensitive.
+.SH RETURN VALUE
+The
+.BR libsimple_memcaseeqlen ()
+function returns the number of bytes
+.I a
+and
+.I b
+have in common at their beginnings.
+.SH ERRORS
+The
+.BR libsimple_memcaseeqlen ()
+function cannot fail.
+.SH ATTRIBUTES
+For an explanation of the terms used in this section, see
+.BR attributes (7).
+.TS
+allbox;
+lb lb lb
+l l l.
+Interface	Attribute	Value
+T{
+.BR libsimple_memcaseeqlen ()
+T}	Thread safety	MT-Safe
+T{
+.BR libsimple_memcaseeqlen ()
+T}	Async-signal safety	AS-Safe
+T{
+.BR libsimple_memcaseeqlen ()
+T}	Async-cancel safety	AC-Safe
+.TE
+.SH EXAMPLES
+None.
+.SH APPLICATION USAGE
+None.
+.SH RATIONALE
+None.
+.SH FUTURE DIRECTIONS
+None.
+.SH NOTES
+None.
+.SH BUGS
+None.
+.SH SEE ALSO
+.BR libsimple_memeqlen (3),
+.BR libsimple_memrcaseeqlen (3)
diff --git a/man/libsimple_memelem.3 b/man/libsimple_memelem.3
index 5e54171..833e246 100644
--- a/man/libsimple_memelem.3
+++ b/man/libsimple_memelem.3
@@ -11,7 +11,7 @@ void *libsimple_memelem(const void *\fIhaystack\fP, size_t \fInhaystack\fP, cons
 # define memelem libsimple_memelem
 #endif
 .fi
-
+.PP
 Link with
 .IR \-lsimple .
 .SH DESCRIPTION
@@ -27,6 +27,8 @@ with the size
 .IR nneedle ,
 and with an offset equivalent to zero modulo
 .IR nneedle .
+.PP
+The comparison is case-sensitive.
 .SH RETURN VALUE
 The
 .BR libsimple_memelem ()
diff --git a/man/libsimple_memends.3 b/man/libsimple_memends.3
index 114cedb..8ab4f81 100644
--- a/man/libsimple_memends.3
+++ b/man/libsimple_memends.3
@@ -11,7 +11,7 @@ void *libsimple_memends(const void *\fIs\fP, size_t \fIn\fP, const void *\fIt\fP
 # define memends libsimple_memends
 #endif
 .fi
-
+.PP
 Link with
 .IR \-lsimple .
 .SH DESCRIPTION
@@ -31,6 +31,8 @@ is the same as the
 .I m
 first bytes of
 .IR t .
+.PP
+The comparison is case-sensitive.
 .SH RETURN VALUE
 The
 .BR libsimple_memends ()
diff --git a/man/libsimple_memeq.3 b/man/libsimple_memeq.3
index fa1ac20..1deca9c 100644
--- a/man/libsimple_memeq.3
+++ b/man/libsimple_memeq.3
@@ -11,7 +11,7 @@ void *libsimple_memeq(const void *\fIa\fP, const void *\fIb\fP, size_t \fIn\fP);
 # define memeq libsimple_memeq
 #endif
 .fi
-
+.PP
 Link with
 .IR \-lsimple .
 .SH DESCRIPTION
@@ -24,6 +24,8 @@ bytes of
 and
 .I b
 are equal.
+.PP
+The comparison is case-sensitive.
 .SH RETURN VALUE
 The
 .BR libsimple_memeq ()
@@ -67,4 +69,5 @@ None.
 .SH BUGS
 None.
 .SH SEE ALSO
+.BR libsimple_memeqlen (3),
 .BR memcmp (3)
diff --git a/man/libsimple_memeqlen.3 b/man/libsimple_memeqlen.3
new file mode 100644
index 0000000..6ef9121
--- /dev/null
+++ b/man/libsimple_memeqlen.3
@@ -0,0 +1,75 @@
+.TH LIBSIMPLE_MEMEQLEN 3 2018-10-21 libsimple
+.SH NAME
+libsimple_memeqlen \- check initial commonality
+.SH SYNOPSIS
+.nf
+#include <libsimple.h>
+
+size_t libsimple_memeqlen(const void *\fIa\fP, size_t \fIn\fP, const void *\fIb\fP, size_t \fIm\fP);
+
+#ifndef memeqlen
+# define memeqlen libsimple_memeqlen
+#endif
+.fi
+.PP
+Link with
+.IR \-lsimple .
+.SH DESCRIPTION
+The
+.BR libsimple_memeqlen ()
+function scans the number of bytes the byte array
+.IR a ,
+with size
+.IR n ,
+have in common the byte array
+.IR b ,
+with size
+.IR m ,
+at their beginnings.
+.PP
+The comparison is case-sensitive.
+.SH RETURN VALUE
+The
+.BR libsimple_memeqlen ()
+function returns the number of bytes
+.I a
+and
+.I b
+have in common at their beginnings.
+.SH ERRORS
+The
+.BR libsimple_memeqlen ()
+function cannot fail.
+.SH ATTRIBUTES
+For an explanation of the terms used in this section, see
+.BR attributes (7).
+.TS
+allbox;
+lb lb lb
+l l l.
+Interface	Attribute	Value
+T{
+.BR libsimple_memeqlen ()
+T}	Thread safety	MT-Safe
+T{
+.BR libsimple_memeqlen ()
+T}	Async-signal safety	AS-Safe
+T{
+.BR libsimple_memeqlen ()
+T}	Async-cancel safety	AC-Safe
+.TE
+.SH EXAMPLES
+None.
+.SH APPLICATION USAGE
+None.
+.SH RATIONALE
+None.
+.SH FUTURE DIRECTIONS
+None.
+.SH NOTES
+None.
+.SH BUGS
+None.
+.SH SEE ALSO
+.BR libsimple_memcaseeqlen (3),
+.BR libsimple_memreqlen (3)
diff --git a/man/libsimple_memmem.3 b/man/libsimple_memmem.3
index 18dec5d..15437cd 100644
--- a/man/libsimple_memmem.3
+++ b/man/libsimple_memmem.3
@@ -11,7 +11,7 @@ void *libsimple_memmem(const void *\fIhaystack\fP, size_t \fInhaystack\fP, const
 # define memmem libsimple_memmem
 #endif
 .fi
-
+.PP
 Link with
 .IR \-lsimple .
 .SH DESCRIPTION
@@ -25,6 +25,8 @@ for the first occurence of the byte string
 .I needle
 with the size
 .IR nneedle .
+.PP
+The comparison is case-sensitive.
 .SH RETURN VALUE
 The
 .BR libsimple_memmem ()
diff --git a/man/libsimple_mempcpy.3 b/man/libsimple_mempcpy.3
index 4d4c514..26531b5 100644
--- a/man/libsimple_mempcpy.3
+++ b/man/libsimple_mempcpy.3
@@ -11,7 +11,7 @@ void *libsimple_mempcpy(void *\fIdest\fP, const void *\fIsrc\fP, size_t \fIn\fP)
 # define mempcpy libsimple_mempcpy
 #endif
 .fi
-
+.PP
 Link with
 .IR \-lsimple .
 .SH DESCRIPTION
diff --git a/man/libsimple_mempset.3 b/man/libsimple_mempset.3
index 33b610c..f75e424 100644
--- a/man/libsimple_mempset.3
+++ b/man/libsimple_mempset.3
@@ -11,7 +11,7 @@ void *libsimple_mempset(void *\fIs\fP, int \fIc\fP, size_t \fIn\fP);
 # define mempset libsimple_mempset
 #endif
 .fi
-
+.PP
 Link with
 .IR \-lsimple .
 .SH DESCRIPTION
diff --git a/man/libsimple_mempsetelem.3 b/man/libsimple_mempsetelem.3
index ca52a2e..0b32228 100644
--- a/man/libsimple_mempsetelem.3
+++ b/man/libsimple_mempsetelem.3
@@ -11,7 +11,7 @@ void *libsimple_mempsetelem(void *\fIbuf\fP, const void *\fIitem\fP, size_t \fIs
 # define mempsetelem libsimple_mempsetelem
 #endif
 .fi
-
+.PP
 Link with
 .IR \-lsimple .
 .SH DESCRIPTION
diff --git a/man/libsimple_memrcaseeqlen.3 b/man/libsimple_memrcaseeqlen.3
new file mode 100644
index 0000000..ce6838c
--- /dev/null
+++ b/man/libsimple_memrcaseeqlen.3
@@ -0,0 +1,75 @@
+.TH LIBSIMPLE_MEMRCASEEQLEN 3 2018-10-21 libsimple
+.SH NAME
+libsimple_memrcaseeqlen \- check terminal commonality
+.SH SYNOPSIS
+.nf
+#include <libsimple.h>
+
+size_t libsimple_memrcaseeqlen(const void *\fIa\fP, size_t \fIn\fP, const void *\fIb\fP, size_t \fIm\fP);
+
+#ifndef memrcaseeqlen
+# define memrcaseeqlen libsimple_memrcaseeqlen
+#endif
+.fi
+.PP
+Link with
+.IR \-lsimple .
+.SH DESCRIPTION
+The
+.BR libsimple_memrcaseeqlen ()
+function scans the number of bytes the byte array
+.IR a ,
+with size
+.IR n ,
+have in common the byte array
+.IR b ,
+with size
+.IR m ,
+at their ends.
+.PP
+The comparison is case-insensitive.
+.SH RETURN VALUE
+The
+.BR libsimple_memrcaseeqlen ()
+function returns the number of bytes
+.I a
+and
+.I b
+have in common at their ends.
+.SH ERRORS
+The
+.BR libsimple_memrcaseeqlen ()
+function cannot fail.
+.SH ATTRIBUTES
+For an explanation of the terms used in this section, see
+.BR attributes (7).
+.TS
+allbox;
+lb lb lb
+l l l.
+Interface	Attribute	Value
+T{
+.BR libsimple_memrcaseeqlen ()
+T}	Thread safety	MT-Safe
+T{
+.BR libsimple_memrcaseeqlen ()
+T}	Async-signal safety	AS-Safe
+T{
+.BR libsimple_memrcaseeqlen ()
+T}	Async-cancel safety	AC-Safe
+.TE
+.SH EXAMPLES
+None.
+.SH APPLICATION USAGE
+None.
+.SH RATIONALE
+None.
+.SH FUTURE DIRECTIONS
+None.
+.SH NOTES
+None.
+.SH BUGS
+None.
+.SH SEE ALSO
+.BR libsimple_memreqlen (3),
+.BR libsimple_memcaseeqlen (3)
diff --git a/man/libsimple_memrchr.3 b/man/libsimple_memrchr.3
index b0a01a7..8fd74f7 100644
--- a/man/libsimple_memrchr.3
+++ b/man/libsimple_memrchr.3
@@ -11,7 +11,7 @@ void *libsimple_memrchr(const void *\fIs\fP, int \fIc\fP, size_t \fIn\fP);
 # define memrchr libsimple_memrchr
 #endif
 .fi
-
+.PP
 Link with
 .IR \-lsimple .
 .SH DESCRIPTION
@@ -25,6 +25,8 @@ for the last occurence of the byte
 .I c
 (it is converted to a
 .BR char ).
+.PP
+The comparison is case-sensitive.
 .SH RETURN VALUE
 The
 .BR libsimple_memrchr ()
diff --git a/man/libsimple_memrelem.3 b/man/libsimple_memrelem.3
index 66f7bd8..203ffee 100644
--- a/man/libsimple_memrelem.3
+++ b/man/libsimple_memrelem.3
@@ -11,7 +11,7 @@ void *libsimple_memrelem(const void *\fIhaystack\fP, size_t \fInhaystack\fP, con
 # define memrelem libsimple_memrelem
 #endif
 .fi
-
+.PP
 Link with
 .IR \-lsimple .
 .SH DESCRIPTION
@@ -27,6 +27,8 @@ with the size
 .IR nneedle ,
 and with an offset equivalent to zero modulo
 .IR nneedle .
+.PP
+The comparison is case-sensitive.
 .SH RETURN VALUE
 The
 .BR libsimple_memrelem ()
diff --git a/man/libsimple_memreqlen.3 b/man/libsimple_memreqlen.3
new file mode 100644
index 0000000..80ae98e
--- /dev/null
+++ b/man/libsimple_memreqlen.3
@@ -0,0 +1,75 @@
+.TH LIBSIMPLE_MEMREQLEN 3 2018-10-21 libsimple
+.SH NAME
+libsimple_memreqlen \- check terminal commonality
+.SH SYNOPSIS
+.nf
+#include <libsimple.h>
+
+size_t libsimple_memreqlen(const void *\fIa\fP, size_t \fIn\fP, const void *\fIb\fP, size_t \fIm\fP);
+
+#ifndef memreqlen
+# define memreqlen libsimple_memreqlen
+#endif
+.fi
+.PP
+Link with
+.IR \-lsimple .
+.SH DESCRIPTION
+The
+.BR libsimple_memreqlen ()
+function scans the number of bytes the byte array
+.IR a ,
+with size
+.IR n ,
+have in common the byte array
+.IR b ,
+with size
+.IR m ,
+at their ends.
+.PP
+The comparison is case-sensitive.
+.SH RETURN VALUE
+The
+.BR libsimple_memreqlen ()
+function returns the number of bytes
+.I a
+and
+.I b
+have in common at their ends.
+.SH ERRORS
+The
+.BR libsimple_memreqlen ()
+function cannot fail.
+.SH ATTRIBUTES
+For an explanation of the terms used in this section, see
+.BR attributes (7).
+.TS
+allbox;
+lb lb lb
+l l l.
+Interface	Attribute	Value
+T{
+.BR libsimple_memreqlen ()
+T}	Thread safety	MT-Safe
+T{
+.BR libsimple_memreqlen ()
+T}	Async-signal safety	AS-Safe
+T{
+.BR libsimple_memreqlen ()
+T}	Async-cancel safety	AC-Safe
+.TE
+.SH EXAMPLES
+None.
+.SH APPLICATION USAGE
+None.
+.SH RATIONALE
+None.
+.SH FUTURE DIRECTIONS
+None.
+.SH NOTES
+None.
+.SH BUGS
+None.
+.SH SEE ALSO
+.BR libsimple_memrcaseeqlen (3),
+.BR libsimple_memeqlen (3)
diff --git a/man/libsimple_memrmem.3 b/man/libsimple_memrmem.3
index aae6572..8ee94c2 100644
--- a/man/libsimple_memrmem.3
+++ b/man/libsimple_memrmem.3
@@ -11,7 +11,7 @@ void *libsimple_memrmem(const void *\fIhaystack\fP, size_t \fInhaystack\fP, cons
 # define memrmem libsimple_memrmem
 #endif
 .fi
-
+.PP
 Link with
 .IR \-lsimple .
 .SH DESCRIPTION
@@ -25,6 +25,8 @@ for the last occurence of the byte string
 .I needle
 with the size
 .IR nneedle .
+.PP
+The comparison is case-sensitive.
 .SH RETURN VALUE
 The
 .BR libsimple_memrmem ()
diff --git a/man/libsimple_memsetelem.3 b/man/libsimple_memsetelem.3
index 700310a..516a20b 100644
--- a/man/libsimple_memsetelem.3
+++ b/man/libsimple_memsetelem.3
@@ -11,7 +11,7 @@ static inline void *libsimple_memsetelem(void *\fIbuf\fP, const void *\fIitem\fP
 # define memsetelem libsimple_memsetelem
 #endif
 .fi
-
+.PP
 Link with
 .IR \-lsimple .
 .SH DESCRIPTION
diff --git a/man/libsimple_memstarts.3 b/man/libsimple_memstarts.3
index e5e183b..13713a2 100644
--- a/man/libsimple_memstarts.3
+++ b/man/libsimple_memstarts.3
@@ -11,7 +11,7 @@ void *libsimple_memstarts(const void *\fIs\fP, size_t \fIn\fP, const void *\fIt\
 # define memstarts libsimple_memstarts
 #endif
 .fi
-
+.PP
 Link with
 .IR \-lsimple .
 .SH DESCRIPTION
@@ -29,6 +29,8 @@ is the same as the
 .I m
 first bytes of
 .IR t .
+.PP
+The comparison is case-sensitive.
 .SH RETURN VALUE
 The
 .BR libsimple_memstarts ()
diff --git a/man/libsimple_rawmemchr.3 b/man/libsimple_rawmemchr.3
index 2991b1f..4126fbb 100644
--- a/man/libsimple_rawmemchr.3
+++ b/man/libsimple_rawmemchr.3
@@ -11,7 +11,7 @@ void *libsimple_rawmemchr(const void *\fIs\fP, int \fIc\fP);
 # define rawmemchr libsimple_rawmemchr
 #endif
 .fi
-
+.PP
 Link with
 .IR \-lsimple .
 .SH DESCRIPTION
@@ -29,6 +29,8 @@ The
 function assumes there is at least one
 occurence, its behaviour is undefined
 if this is not the case.
+.PP
+The comparison is case-sensitive.
 .SH RETURN VALUE
 The
 .BR libsimple_rawmemchr ()
diff --git a/man/libsimple_rawmemrchr.3 b/man/libsimple_rawmemrchr.3
index c445794..198daa6 100644
--- a/man/libsimple_rawmemrchr.3
+++ b/man/libsimple_rawmemrchr.3
@@ -11,7 +11,7 @@ void *libsimple_rawmemrchr(const void *s, int c, size_t n);
 # define rawmemrchr libsimple_rawmemrchr
 #endif
 .fi
-
+.PP
 Link with
 .IR \-lsimple .
 .SH DESCRIPTION
@@ -31,6 +31,8 @@ The
 function assumes there is at least one
 occurence, its behaviour is undefined
 if this is not the case.
+.PP
+The comparison is case-sensitive.
 .SH RETURN VALUE
 The
 .BR libsimple_rawmemrchr ()
diff --git a/man/libsimple_strcasechr.3 b/man/libsimple_strcasechr.3
index f100ac8..c7cc780 100644
--- a/man/libsimple_strcasechr.3
+++ b/man/libsimple_strcasechr.3
@@ -11,7 +11,7 @@ char *libsimple_strcasechr(const char *\fIs\fP, int \fIc\fP);
 # define strcasechr libsimple_strcasechr
 #endif
 .fi
-
+.PP
 Link with
 .IR \-lsimple .
 .SH DESCRIPTION
diff --git a/man/libsimple_strcasechrnul.3 b/man/libsimple_strcasechrnul.3
index a92387d..81bdc7a 100644
--- a/man/libsimple_strcasechrnul.3
+++ b/man/libsimple_strcasechrnul.3
@@ -11,7 +11,7 @@ char *libsimple_strcasechrnul(const char *\fIs\fP, int \fIc\fP);
 # define strcasechrnul libsimple_strcasechrnul
 #endif
 .fi
-
+.PP
 Link with
 .IR \-lsimple .
 .SH DESCRIPTION
diff --git a/man/libsimple_strcasecmpnul.3 b/man/libsimple_strcasecmpnul.3
index ffd0f8d..e07b551 100644
--- a/man/libsimple_strcasecmpnul.3
+++ b/man/libsimple_strcasecmpnul.3
@@ -11,7 +11,7 @@ static inline int libsimple_strcasecmpnul(const char *\fIa\fP, const char *\fIb\
 # define strcasecmpnul libsimple_strcasecmpnul
 #endif
 .fi
-
+.PP
 Link with
 .IR \-lsimple .
 .SH DESCRIPTION
diff --git a/man/libsimple_strcaseends.3 b/man/libsimple_strcaseends.3
index 4a792a3..ff9a578 100644
--- a/man/libsimple_strcaseends.3
+++ b/man/libsimple_strcaseends.3
@@ -11,7 +11,7 @@ int libsimple_strcaseends(const char *\fIs\fP, const char *\fIt\fP);
 # define strcaseends libsimple_strcaseends
 #endif
 .fi
-
+.PP
 Link with
 .IR \-lsimple .
 .SH DESCRIPTION
diff --git a/man/libsimple_strcaseeq.3 b/man/libsimple_strcaseeq.3
index 41fb3c1..d38b439 100644
--- a/man/libsimple_strcaseeq.3
+++ b/man/libsimple_strcaseeq.3
@@ -11,7 +11,7 @@ static inline int libsimple_strcaseeq(const char *\fIa\fP, const char *\fIb\fP);
 # define strcaseeq libsimple_strcaseeq
 #endif
 .fi
-
+.PP
 Link with
 .IR \-lsimple .
 .SH DESCRIPTION
@@ -69,4 +69,5 @@ None.
 .SH SEE ALSO
 .BR libsimple_strcaseeqnul (3),
 .BR libsimple_streq (3),
+.BR libsimple_strcaseeqlen (3),
 .BR strcasecmp (3)
diff --git a/man/libsimple_strcaseeqlen.3 b/man/libsimple_strcaseeqlen.3
new file mode 100644
index 0000000..6ff8e18
--- /dev/null
+++ b/man/libsimple_strcaseeqlen.3
@@ -0,0 +1,71 @@
+.TH LIBSIMPLE_STRCASEEQLEN 3 2018-10-21 libsimple
+.SH NAME
+libsimple_strcaseeqlen \- check initial commonality
+.SH SYNOPSIS
+.nf
+#include <libsimple.h>
+
+size_t libsimple_strcaseeqlen(const char *\fIa\fP, const char *\fIb\fP);
+
+#ifndef memrcaseeqlen
+# define memrcaseeqlen libsimple_strcaseeqlen
+#endif
+.fi
+.PP
+Link with
+.IR \-lsimple .
+.SH DESCRIPTION
+The
+.BR libsimple_strcaseeqlen ()
+function scans the number of bytes the string
+.I a
+have in common the string
+.I b
+at their beginnings.
+.PP
+The comparison is case-insensitive.
+.SH RETURN VALUE
+The
+.BR libsimple_strcaseeqlen ()
+function returns the number of bytes
+.I a
+and
+.I b
+have in common at their beginnings.
+.SH ERRORS
+The
+.BR libsimple_strcaseeqlen ()
+function cannot fail.
+.SH ATTRIBUTES
+For an explanation of the terms used in this section, see
+.BR attributes (7).
+.TS
+allbox;
+lb lb lb
+l l l.
+Interface	Attribute	Value
+T{
+.BR libsimple_strcaseeqlen ()
+T}	Thread safety	MT-Safe
+T{
+.BR libsimple_strcaseeqlen ()
+T}	Async-signal safety	AS-Safe
+T{
+.BR libsimple_strcaseeqlen ()
+T}	Async-cancel safety	AC-Safe
+.TE
+.SH EXAMPLES
+None.
+.SH APPLICATION USAGE
+None.
+.SH RATIONALE
+None.
+.SH FUTURE DIRECTIONS
+None.
+.SH NOTES
+None.
+.SH BUGS
+None.
+.SH SEE ALSO
+.BR libsimple_streqlen (3),
+.BR libsimple_strrcaseeqlen (3)
diff --git a/man/libsimple_strcaseeqnul.3 b/man/libsimple_strcaseeqnul.3
index ab06c67..17edb4b 100644
--- a/man/libsimple_strcaseeqnul.3
+++ b/man/libsimple_strcaseeqnul.3
@@ -11,7 +11,7 @@ static inline int libsimple_strcaseeqnul(const char *\fIa\fP, const char *\fIb\f
 # define strcaseeqnul libsimple_strcaseeqnul
 #endif
 .fi
-
+.PP
 Link with
 .IR \-lsimple .
 .SH DESCRIPTION
diff --git a/man/libsimple_strcasestarts.3 b/man/libsimple_strcasestarts.3
index 9b7081f..c36ac4a 100644
--- a/man/libsimple_strcasestarts.3
+++ b/man/libsimple_strcasestarts.3
@@ -11,7 +11,7 @@ static inline int libsimple_strcasestarts(const char *\fIs\fP, const char *\fIt\
 # define strcasestarts libsimple_strcasestarts
 #endif
 .fi
-
+.PP
 Link with
 .IR \-lsimple .
 .SH DESCRIPTION
diff --git a/man/libsimple_strcasestr.3 b/man/libsimple_strcasestr.3
index 346a17b..fe8c6bb 100644
--- a/man/libsimple_strcasestr.3
+++ b/man/libsimple_strcasestr.3
@@ -11,7 +11,7 @@ char *libsimple_strcasestr(const char *\fIhaystack\fP, const char *\fIneedle\fP)
 # define strcasestr libsimple_strcasestr
 #endif
 .fi
-
+.PP
 Link with
 .IR \-lsimple .
 .SH DESCRIPTION
diff --git a/man/libsimple_strchrnul.3 b/man/libsimple_strchrnul.3
index 8d8f53a..0ed76d9 100644
--- a/man/libsimple_strchrnul.3
+++ b/man/libsimple_strchrnul.3
@@ -11,7 +11,7 @@ char *libsimple_strchrnul(const char *\fIs\fP, int \fIc\fP);
 # define strchrnul libsimple_strchrnul
 #endif
 .fi
-
+.PP
 Link with
 .IR \-lsimple .
 .SH DESCRIPTION
diff --git a/man/libsimple_strcmpnul.3 b/man/libsimple_strcmpnul.3
index 79c53bf..ea962d7 100644
--- a/man/libsimple_strcmpnul.3
+++ b/man/libsimple_strcmpnul.3
@@ -11,7 +11,7 @@ static inline int libsimple_strcmpnul(const char *\fIa\fP, const char *\fIb\fP);
 # define strcmpnul libsimple_strcmpnul
 #endif
 .fi
-
+.PP
 Link with
 .IR \-lsimple .
 .SH DESCRIPTION
diff --git a/man/libsimple_strend.3 b/man/libsimple_strend.3
index 1ceb9ac..e1652b6 100644
--- a/man/libsimple_strend.3
+++ b/man/libsimple_strend.3
@@ -11,7 +11,7 @@ static inline char *libsimple_strend(const char *\fIs\fP);
 # define strend libsimple_strend
 #endif
 .fi
-
+.PP
 Link with
 .IR \-lsimple .
 .SH DESCRIPTION
diff --git a/man/libsimple_strends.3 b/man/libsimple_strends.3
index abc7e5a..e7b9088 100644
--- a/man/libsimple_strends.3
+++ b/man/libsimple_strends.3
@@ -11,7 +11,7 @@ int libsimple_strends(const char *\fIs\fP, const char *\fIt\fP);
 # define strends libsimple_strends
 #endif
 .fi
-
+.PP
 Link with
 .IR \-lsimple .
 .SH DESCRIPTION
diff --git a/man/libsimple_streq.3 b/man/libsimple_streq.3
index f8d28fb..7904860 100644
--- a/man/libsimple_streq.3
+++ b/man/libsimple_streq.3
@@ -11,7 +11,7 @@ static inline int libsimple_streq(const char *\fIa\fP, const char *\fIb\fP);
 # define streq libsimple_streq
 #endif
 .fi
-
+.PP
 Link with
 .IR \-lsimple .
 .SH DESCRIPTION
@@ -68,4 +68,6 @@ None.
 .SH SEE ALSO
 .BR libsimple_streqnul (3),
 .BR libsimple_strcaseeq (3),
+.BR libsimple_strcaseeq (3),
+.BR libsimple_streqlen (3),
 .BR strcmp (3)
diff --git a/man/libsimple_streqlen.3 b/man/libsimple_streqlen.3
new file mode 100644
index 0000000..78fee3e
--- /dev/null
+++ b/man/libsimple_streqlen.3
@@ -0,0 +1,71 @@
+.TH LIBSIMPLE_STREQLEN 3 2018-10-21 libsimple
+.SH NAME
+libsimple_streqlen \- check initial commonality
+.SH SYNOPSIS
+.nf
+#include <libsimple.h>
+
+size_t libsimple_streqlen(const char *\fIa\fP, const char *\fIb\fP);
+
+#ifndef memrcaseeqlen
+# define memrcaseeqlen libsimple_streqlen
+#endif
+.fi
+.PP
+Link with
+.IR \-lsimple .
+.SH DESCRIPTION
+The
+.BR libsimple_streqlen ()
+function scans the number of bytes the string
+.I a
+have in common the string
+.I b
+at their beginnings.
+.PP
+The comparison is case-sensitive.
+.SH RETURN VALUE
+The
+.BR libsimple_streqlen ()
+function returns the number of bytes
+.I a
+and
+.I b
+have in common at their beginnings.
+.SH ERRORS
+The
+.BR libsimple_streqlen ()
+function cannot fail.
+.SH ATTRIBUTES
+For an explanation of the terms used in this section, see
+.BR attributes (7).
+.TS
+allbox;
+lb lb lb
+l l l.
+Interface	Attribute	Value
+T{
+.BR libsimple_streqlen ()
+T}	Thread safety	MT-Safe
+T{
+.BR libsimple_streqlen ()
+T}	Async-signal safety	AS-Safe
+T{
+.BR libsimple_streqlen ()
+T}	Async-cancel safety	AC-Safe
+.TE
+.SH EXAMPLES
+None.
+.SH APPLICATION USAGE
+None.
+.SH RATIONALE
+None.
+.SH FUTURE DIRECTIONS
+None.
+.SH NOTES
+None.
+.SH BUGS
+None.
+.SH SEE ALSO
+.BR libsimple_strreqlen (3),
+.BR libsimple_strcaseeqlen (3)
diff --git a/man/libsimple_streqnul.3 b/man/libsimple_streqnul.3
index fa0a35e..df39a67 100644
--- a/man/libsimple_streqnul.3
+++ b/man/libsimple_streqnul.3
@@ -11,7 +11,7 @@ static inline int libsimple_streqnul(const char *\fIa\fP, const char *\fIb\fP);
 # define streqnul libsimple_streqnul
 #endif
 .fi
-
+.PP
 Link with
 .IR \-lsimple .
 .SH DESCRIPTION
diff --git a/man/libsimple_strrcasechr.3 b/man/libsimple_strrcasechr.3
index 188bcd7..65382e6 100644
--- a/man/libsimple_strrcasechr.3
+++ b/man/libsimple_strrcasechr.3
@@ -11,7 +11,7 @@ char *libsimple_strrcasechr(const char *\fIs\fP, int \fIc\fP);
 # define strrcasechr libsimple_strrcasechr
 #endif
 .fi
-
+.PP
 Link with
 .IR \-lsimple .
 .SH DESCRIPTION
diff --git a/man/libsimple_strrcaseeqlen.3 b/man/libsimple_strrcaseeqlen.3
new file mode 100644
index 0000000..429393f
--- /dev/null
+++ b/man/libsimple_strrcaseeqlen.3
@@ -0,0 +1,71 @@
+.TH LIBSIMPLE_STRRCASEEQLEN 3 2018-10-21 libsimple
+.SH NAME
+libsimple_strrcaseeqlen \- check terminal commonality
+.SH SYNOPSIS
+.nf
+#include <libsimple.h>
+
+size_t libsimple_strrcaseeqlen(const char *\fIa\fP, const char *\fIb\fP);
+
+#ifndef strrcaseeqlen
+# define strrcaseeqlen libsimple_strrcaseeqlen
+#endif
+.fi
+.PP
+Link with
+.IR \-lsimple .
+.SH DESCRIPTION
+The
+.BR libsimple_strrcaseeqlen ()
+function scans the number of bytes the string
+.I a
+have in common the string
+.I b
+at their ends.
+.PP
+The comparison is case-insensitive.
+.SH RETURN VALUE
+The
+.BR libsimple_strrcaseeqlen ()
+function returns the number of bytes
+.I a
+and
+.I b
+have in common at their ends.
+.SH ERRORS
+The
+.BR libsimple_strrcaseeqlen ()
+function cannot fail.
+.SH ATTRIBUTES
+For an explanation of the terms used in this section, see
+.BR attributes (7).
+.TS
+allbox;
+lb lb lb
+l l l.
+Interface	Attribute	Value
+T{
+.BR libsimple_strrcaseeqlen ()
+T}	Thread safety	MT-Safe
+T{
+.BR libsimple_strrcaseeqlen ()
+T}	Async-signal safety	AS-Safe
+T{
+.BR libsimple_strrcaseeqlen ()
+T}	Async-cancel safety	AC-Safe
+.TE
+.SH EXAMPLES
+None.
+.SH APPLICATION USAGE
+None.
+.SH RATIONALE
+None.
+.SH FUTURE DIRECTIONS
+None.
+.SH NOTES
+None.
+.SH BUGS
+None.
+.SH SEE ALSO
+.BR libsimple_strreqlen (3),
+.BR libsimple_strcaseeqlen (3)
diff --git a/man/libsimple_strrcasestr.3 b/man/libsimple_strrcasestr.3
index 3b277ae..4418795 100644
--- a/man/libsimple_strrcasestr.3
+++ b/man/libsimple_strrcasestr.3
@@ -11,7 +11,7 @@ char *libsimple_strrcasestr(const char *\fIhaystack\fP, const char *\fIneedle\fP
 # define strrcasestr libsimple_strrcasestr
 #endif
 .fi
-
+.PP
 Link with
 .IR \-lsimple .
 .SH DESCRIPTION
diff --git a/man/libsimple_strreqlen.3 b/man/libsimple_strreqlen.3
new file mode 100644
index 0000000..e64358d
--- /dev/null
+++ b/man/libsimple_strreqlen.3
@@ -0,0 +1,71 @@
+.TH LIBSIMPLE_STRREQLEN 3 2018-10-21 libsimple
+.SH NAME
+libsimple_strreqlen \- check terminal commonality
+.SH SYNOPSIS
+.nf
+#include <libsimple.h>
+
+size_t libsimple_strreqlen(const char *\fIa\fP, const char *\fIb\fP);
+
+#ifndef strreqlen
+# define strreqlen libsimple_strreqlen
+#endif
+.fi
+.PP
+Link with
+.IR \-lsimple .
+.SH DESCRIPTION
+The
+.BR libsimple_strreqlen ()
+function scans the number of bytes the string
+.I a
+have in common the string
+.I b
+at their ends.
+.PP
+The comparison is case-sensitive.
+.SH RETURN VALUE
+The
+.BR libsimple_strreqlen ()
+function returns the number of bytes
+.I a
+and
+.I b
+have in common at their ends.
+.SH ERRORS
+The
+.BR libsimple_strreqlen ()
+function cannot fail.
+.SH ATTRIBUTES
+For an explanation of the terms used in this section, see
+.BR attributes (7).
+.TS
+allbox;
+lb lb lb
+l l l.
+Interface	Attribute	Value
+T{
+.BR libsimple_strreqlen ()
+T}	Thread safety	MT-Safe
+T{
+.BR libsimple_strreqlen ()
+T}	Async-signal safety	AS-Safe
+T{
+.BR libsimple_strreqlen ()
+T}	Async-cancel safety	AC-Safe
+.TE
+.SH EXAMPLES
+None.
+.SH APPLICATION USAGE
+None.
+.SH RATIONALE
+None.
+.SH FUTURE DIRECTIONS
+None.
+.SH NOTES
+None.
+.SH BUGS
+None.
+.SH SEE ALSO
+.BR libsimple_strreqlen (3),
+.BR libsimple_streqlen (3)
diff --git a/man/libsimple_strrstr.3 b/man/libsimple_strrstr.3
index ad85a54..973f50b 100644
--- a/man/libsimple_strrstr.3
+++ b/man/libsimple_strrstr.3
@@ -11,7 +11,7 @@ char *libsimple_strrstr(const char *\fIhaystack\fP, const char *\fIneedle\fP);
 # define strrstr libsimple_strrstr
 #endif
 .fi
-
+.PP
 Link with
 .IR \-lsimple .
 .SH DESCRIPTION
diff --git a/man/libsimple_strstarts.3 b/man/libsimple_strstarts.3
index cf08967..c277f11 100644
--- a/man/libsimple_strstarts.3
+++ b/man/libsimple_strstarts.3
@@ -11,7 +11,7 @@ int libsimple_strstarts(const char *\fIs\fP, const char *\fIt\fP);
 # define strstarts libsimple_strstarts
 #endif
 .fi
-
+.PP
 Link with
 .IR \-lsimple .
 .SH DESCRIPTION
diff --git a/man/libsimple_vputenvf.3 b/man/libsimple_vputenvf.3
index 3c081e1..db6858e 100644
--- a/man/libsimple_vputenvf.3
+++ b/man/libsimple_vputenvf.3
@@ -31,7 +31,7 @@ static inline void libsimple_eputenvf(const char *\fIfmt\fP, ...);
 # define eputenvf libsimple_eputenvf
 #endif
 .fi
-
+.PP
 Link with
 .IR \-lsimple .
 .SH DESCRIPTION
diff --git a/man/memcaseeqlen.3libsimple b/man/memcaseeqlen.3libsimple
new file mode 120000
index 0000000..5fa4167
--- /dev/null
+++ b/man/memcaseeqlen.3libsimple
@@ -0,0 +1 @@
+libsimple_memcaseeqlen.3
\ No newline at end of file
diff --git a/man/memeqlen.3libsimple b/man/memeqlen.3libsimple
new file mode 120000
index 0000000..73567aa
--- /dev/null
+++ b/man/memeqlen.3libsimple
@@ -0,0 +1 @@
+libsimple_memeqlen.3
\ No newline at end of file
diff --git a/man/memrcaseeqlen.3libsimple b/man/memrcaseeqlen.3libsimple
new file mode 120000
index 0000000..5f451d1
--- /dev/null
+++ b/man/memrcaseeqlen.3libsimple
@@ -0,0 +1 @@
+libsimple_memrcaseeqlen.3
\ No newline at end of file
diff --git a/man/memreqlen.3libsimple b/man/memreqlen.3libsimple
new file mode 120000
index 0000000..fd637c4
--- /dev/null
+++ b/man/memreqlen.3libsimple
@@ -0,0 +1 @@
+libsimple_memreqlen.3
\ No newline at end of file
diff --git a/man/strcaseeqlen.3libsimple b/man/strcaseeqlen.3libsimple
new file mode 120000
index 0000000..36f0971
--- /dev/null
+++ b/man/strcaseeqlen.3libsimple
@@ -0,0 +1 @@
+libsimple_strcaseeqlen.3
\ No newline at end of file
diff --git a/man/streqlen.3libsimple b/man/streqlen.3libsimple
new file mode 120000
index 0000000..85b2736
--- /dev/null
+++ b/man/streqlen.3libsimple
@@ -0,0 +1 @@
+libsimple_streqlen.3
\ No newline at end of file
diff --git a/man/strrcaseeqlen.3libsimple b/man/strrcaseeqlen.3libsimple
new file mode 120000
index 0000000..698634c
--- /dev/null
+++ b/man/strrcaseeqlen.3libsimple
@@ -0,0 +1 @@
+libsimple_strrcaseeqlen.3
\ No newline at end of file
diff --git a/man/strreqlen.3libsimple b/man/strreqlen.3libsimple
new file mode 120000
index 0000000..0be1d93
--- /dev/null
+++ b/man/strreqlen.3libsimple
@@ -0,0 +1 @@
+libsimple_strreqlen.3
\ No newline at end of file
diff --git a/memcaseeqlen.c b/memcaseeqlen.c
new file mode 100644
index 0000000..79ab198
--- /dev/null
+++ b/memcaseeqlen.c
@@ -0,0 +1,42 @@
+/* See LICENSE file for copyright and license details. */
+#include "libsimple.h"
+#ifndef TEST
+
+
+size_t
+libsimple_memcaseeqlen(const void *a_, size_t n, const void *b_, size_t m)
+{
+	const char *a = a_, *b = b_;
+	size_t i = 0;
+	n = n < m ? n : m;
+	for (; i < n && tolower(a[i]) == tolower(b[i]); i++);
+	return i;
+}
+
+
+#else
+#include "test.h"
+
+int
+main(void)
+{
+	char s[] = "abcdefgh", t[] = "ABCDEFGH";
+	size_t i, j;
+	assert(libsimple_memcaseeqlen("x", 0, "x", 0) == 0);
+	assert(libsimple_memcaseeqlen("x", 1, "x", 0) == 0);
+	assert(libsimple_memcaseeqlen("x", 1, "y", 1) == 0);
+	assert(libsimple_memcaseeqlen("y", 0, "y", 1) == 0);
+	for (i = 0; i <= 8; i++) {
+		for (j = 0; j <= 8; j++) {
+			assert(libsimple_memcaseeqlen(&s[i], 8 - i, &t[j], 8 - j) == (i == j ? 8 - i : 0));
+			assert(libsimple_memcaseeqlen(s, i, t, j) == (i < j ? i : j));
+			assert(libsimple_memcaseeqlen(&t[i], 8 - i, &s[j], 8 - j) == (i == j ? 8 - i : 0));
+			assert(libsimple_memcaseeqlen(t, i, s, j) == (i < j ? i : j));
+		}
+	}
+	assert(libsimple_memcaseeqlen("abc", 3, "abc", 3) == 3);
+	assert(libsimple_memcaseeqlen("123", 3, "123", 3) == 3);
+	return 0;
+}
+
+#endif
diff --git a/memeqlen.c b/memeqlen.c
new file mode 100644
index 0000000..f5a214c
--- /dev/null
+++ b/memeqlen.c
@@ -0,0 +1,40 @@
+/* See LICENSE file for copyright and license details. */
+#include "libsimple.h"
+#ifndef TEST
+
+
+size_t
+libsimple_memeqlen(const void *a_, size_t n, const void *b_, size_t m)
+{
+	const char *a = a_, *b = b_;
+	size_t i = 0;
+	n = n < m ? n : m;
+	for (; i < n && a[i] == b[i]; i++);
+	return i;
+}
+
+
+#else
+#include "test.h"
+
+int
+main(void)
+{
+	char s[] = "abcdefgh", t[] = "abcdefgh";
+	size_t i, j;
+	assert(libsimple_memeqlen("x", 0, "x", 0) == 0);
+	assert(libsimple_memeqlen("x", 1, "x", 0) == 0);
+	assert(libsimple_memeqlen("x", 1, "y", 1) == 0);
+	assert(libsimple_memeqlen("y", 0, "y", 1) == 0);
+	for (i = 0; i <= 8; i++) {
+		for (j = 0; j <= 8; j++) {
+			assert(libsimple_memeqlen(&s[i], 8 - i, &t[j], 8 - j) == (i == j ? 8 - i : 0));
+			assert(libsimple_memeqlen(s, i, t, j) == (i < j ? i : j));
+		}
+	}
+	assert(libsimple_memeqlen("abc", 3, "ABC", 3) == 0);
+	assert(libsimple_memeqlen("123", 3, "123", 3) == 3);
+	return 0;
+}
+
+#endif
diff --git a/memrcaseeqlen.c b/memrcaseeqlen.c
new file mode 100644
index 0000000..3f586b7
--- /dev/null
+++ b/memrcaseeqlen.c
@@ -0,0 +1,41 @@
+/* See LICENSE file for copyright and license details. */
+#include "libsimple.h"
+#ifndef TEST
+
+
+size_t
+libsimple_memrcaseeqlen(const void *a_, size_t n, const void *b_, size_t m)
+{
+	const char *a = &((char *)a_)[n], *b = &((char *)b_)[m];
+	size_t i = 0, len = n < m ? n : m;
+	for (; i < len && (--a, --b, tolower(*a) == tolower(*b)); i++);
+	return i;
+}
+
+
+#else
+#include "test.h"
+
+int
+main(void)
+{
+	char s[] = "abcdefgh", t[] = "ABCDEFGH";
+	size_t i, j;
+	assert(libsimple_memrcaseeqlen("x", 0, "x", 0) == 0);
+	assert(libsimple_memrcaseeqlen("x", 1, "x", 0) == 0);
+	assert(libsimple_memrcaseeqlen("x", 1, "y", 1) == 0);
+	assert(libsimple_memrcaseeqlen("y", 0, "y", 1) == 0);
+	for (i = 0; i <= 8; i++) {
+		for (j = 0; j <= 8; j++) {
+			assert(libsimple_memrcaseeqlen(&s[i], 8 - i, &t[j], 8 - j) == 8 - (i > j ? i : j));
+			assert(libsimple_memrcaseeqlen(s, i, t, j) == (i == j ? i : 0));
+			assert(libsimple_memrcaseeqlen(&t[i], 8 - i, &s[j], 8 - j) == 8 - (i > j ? i : j));
+			assert(libsimple_memrcaseeqlen(t, i, s, j) == (i == j ? i : 0));
+		}
+	}
+	assert(libsimple_memrcaseeqlen("abc", 3, "abc", 3) == 3);
+	assert(libsimple_memrcaseeqlen("123", 3, "123", 3) == 3);
+	return 0;
+}
+
+#endif
diff --git a/memreqlen.c b/memreqlen.c
new file mode 100644
index 0000000..c276b8d
--- /dev/null
+++ b/memreqlen.c
@@ -0,0 +1,39 @@
+/* See LICENSE file for copyright and license details. */
+#include "libsimple.h"
+#ifndef TEST
+
+
+size_t
+libsimple_memreqlen(const void *a_, size_t n, const void *b_, size_t m)
+{
+	const char *a = &((char *)a_)[n], *b = &((char *)b_)[m];
+	size_t i = 0, len = n < m ? n : m;
+	for (; i < len && *--a == *--b; i++);
+	return i;
+}
+
+
+#else
+#include "test.h"
+
+int
+main(void)
+{
+	char s[] = "abcdefgh", t[] = "abcdefgh";
+	size_t i, j;
+	assert(libsimple_memreqlen("x", 0, "x", 0) == 0);
+	assert(libsimple_memreqlen("x", 1, "x", 0) == 0);
+	assert(libsimple_memreqlen("x", 1, "y", 1) == 0);
+	assert(libsimple_memreqlen("y", 0, "y", 1) == 0);
+	for (i = 0; i <= 8; i++) {
+		for (j = 0; j <= 8; j++) {
+			assert(libsimple_memreqlen(&s[i], 8 - i, &t[j], 8 - j) == 8 - (i > j ? i : j));
+			assert(libsimple_memreqlen(s, i, t, j) == (i == j ? i : 0));
+		}
+	}
+	assert(libsimple_memreqlen("abc", 3, "ABC", 3) == 0);
+	assert(libsimple_memreqlen("123", 3, "123", 3) == 3);
+	return 0;
+}
+
+#endif
diff --git a/strcaseeqlen.c b/strcaseeqlen.c
new file mode 100644
index 0000000..625a3ad
--- /dev/null
+++ b/strcaseeqlen.c
@@ -0,0 +1,43 @@
+/* See LICENSE file for copyright and license details. */
+#include "libsimple.h"
+#ifndef TEST
+
+
+size_t
+libsimple_strcaseeqlen(const char *a, const char *b)
+{
+	size_t i = 0;
+	for (; tolower(a[i]) == tolower(b[i]) && a[i]; i++);
+	return i;
+}
+
+
+#else
+#include "test.h"
+
+int
+main(void)
+{
+	char s[] = "abcdefgh", t[] = "ABCDEFGH";
+	size_t i, j;
+	assert(libsimple_strcaseeqlen("", "") == 0);
+	assert(libsimple_strcaseeqlen("x", "") == 0);
+	assert(libsimple_strcaseeqlen("x", "y") == 0);
+	assert(libsimple_strcaseeqlen("", "y") == 0);
+	for (i = 0; i <= 8; i++) {
+		for (j = 0; j <= 8; j++) {
+			assert(libsimple_strcaseeqlen(&s[i], &t[j]) == (i == j ? 8 - i : 0));
+			assert(libsimple_strcaseeqlen(&t[i], &s[j]) == (i == j ? 8 - i : 0));
+			s[i] = t[j] = '\0';
+			assert(libsimple_strcaseeqlen(s, t) == (i < j ? i : j));
+			assert(libsimple_strcaseeqlen(t, s) == (i < j ? i : j));
+			s[i] = "abcdefgh"[i];
+			t[j] = "ABCDEFGH"[j];
+		}
+	}
+	assert(libsimple_strcaseeqlen("abc", "abc") == 3);
+	assert(libsimple_strcaseeqlen("123", "123") == 3);
+	return 0;
+}
+
+#endif
diff --git a/streqlen.c b/streqlen.c
new file mode 100644
index 0000000..d563ecc
--- /dev/null
+++ b/streqlen.c
@@ -0,0 +1,41 @@
+/* See LICENSE file for copyright and license details. */
+#include "libsimple.h"
+#ifndef TEST
+
+
+size_t
+libsimple_streqlen(const char *a, const char *b)
+{
+	size_t i = 0;
+	for (; a[i] == b[i] && a[i]; i++);
+	return i;
+}
+
+
+#else
+#include "test.h"
+
+int
+main(void)
+{
+	char s[] = "abcdefgh", t[] = "abcdefgh";
+	size_t i, j;
+	assert(libsimple_streqlen("", "") == 0);
+	assert(libsimple_streqlen("x", "") == 0);
+	assert(libsimple_streqlen("x", "y") == 0);
+	assert(libsimple_streqlen("", "y") == 0);
+	for (i = 0; i <= 8; i++) {
+		for (j = 0; j <= 8; j++) {
+			assert(libsimple_streqlen(&s[i], &t[j]) == (i == j ? 8 - i : 0));
+			s[i] = t[j] = '\0';
+			assert(libsimple_streqlen(s, t) == (i < j ? i : j));
+			s[i] = "abcdefgh"[i];
+			t[j] = "abcdefgh"[j];
+		}
+	}
+	assert(libsimple_streqlen("abc", "ABC") == 0);
+	assert(libsimple_streqlen("123", "123") == 3);
+	return 0;
+}
+
+#endif