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If applicable, add the following below this CDDL HEADER, with the fields enclosed by brackets "[]" replaced with your own identifying information: Portions Copyright [yyyy] [name of copyright owner] .TH string 9F "27 Feb 2009" "SunOS 5.11" "Kernel Functions for Drivers" .SH NAME string, strcasecmp, strncasecmp, strncat, strlcat, strchr, strrchr, strcmp, strncmp, strcpy, strncpy, strlcpy, strfree, strspn, strdup, ddi_strdup, strlen, strnlen \- string operations .SH SYNOPSIS .LP .nf #include \fBint\fR \fBstrcasecmp\fR(\fBconst char *\fR\fIs1\fR, \fBconst char *\fR\fIs2\fR); .fi .LP .nf \fBint\fR \fBstrncasecmp\fR(\fBconst char *\fR\fIs1\fR, \fBconst char *\fR\fIs2\fR, \fBsize_t\fR \fIn\fR); .fi .LP .nf \fBchar *\fR\fBstrncat\fR(\fBchar *\fR \fIs1\fR, \fBconst char *\fR \fIs2\fR, \fBsize_t\fR \fIn\fR); .fi .LP .nf \fBsize_t\fR \fBstrlcat\fR(\fBchar *\fR\fIdst\fR, \fBconst char *\fR\fIsrc\fR, \fBsize_t\fR \fIdstsize\fR); .fi .LP .nf \fBchar *\fR\fBstrchr\fR(\fBconst char *\fR\fIstr\fR, \fBint\fR \fIchr\fR); .fi .LP .nf \fBchar *\fR\fBstrrchr\fR(\fBconst char *\fR\fIstr\fR, \fBint\fR \fIchr\fR); .fi .LP .nf \fBint\fR \fBstrcmp\fR(\fBconst char *\fR\fIs1\fR, \fBconst char *\fR\fIs2\fR); .fi .LP .nf \fBint\fR \fBstrncmp\fR(\fBconst char *\fR\fIs1\fR, \fBconst char *\fR\fIs2\fR, \fBsize_t\fR \fIn\fR); .fi .LP .nf \fBchar *\fR\fBstrcpy\fR(\fBchar *\fR \fIdst\fR, \fBconst char *\fR \fIsrc\fR); .fi .LP .nf \fBchar *\fR\fBstrncpy\fR(\fBchar *\fR \fIdst\fR, \fBconst char *\fR \fIsrc\fR, \fBsize_t\fR \fIn\fR); .fi .LP .nf \fBsize_t\fR \fBstrlcpy\fR(\fBchar *\fR\fIdst\fR, \fBconst char *\fR\fIsrc\fR, \fBsize_t\fR \fIdstsize\fR); .fi .LP .nf \fBvoid\fR \fBstrfree\fR(\fBchar *\fR\fIs\fR); .fi .LP .nf \fBsize_t\fR \fBstrspn\fR(\fBconst char *\fR\fIs1\fR, \fBconst char *\fR\fIs2\fR); .fi .LP .nf \fBchar *\fR\fBstrdup\fR(\fBconst char *\fR\fIs1\fR); .fi .LP .nf \fBchar *\fR\fBddi_strdup\fR(\fBconst char *\fR\fIs1\fR, \fBint\fR \fIflag\fR); .fi .LP .nf \fBsize_t\fR \fBstrlen\fR(\fBconst char *\fR\fIs\fR); .fi .LP .nf \fBsize_t\fR \fBstrnlen\fR(\fBconst char *\fR\fIs\fR, \fBsize_t\fR \fIn\fR); .fi .SH INTERFACE LEVEL .sp .LP Solaris DDI specific (Solaris DDI). .SH DESCRIPTION .sp .LP The arguments \fIs\fR, \fIs1\fR, and \fIs2\fR point to strings (arrays of characters terminated by a null character). The \fBstrcat()\fR, \fBstrncat()\fR, \fBstrlcat()\fR, \fBstrcpy()\fR, \fBstrncpy()\fR, \fBstrlcpy()\fR, and \fBstrfree()\fR functions all alter their first argument. Additionally, the \fBstrcpy()\fR function does not check for overflow of the array. .SS "\fBstrcasecmp()\fR, \fBstrncasecmp()\fR" .sp .LP The \fBstrcasecmp()\fR and \fBstrncasecmp()\fR functions are case-insensitive versions of \fBstrcmp()\fR and \fBstrncmp()\fR respectively, described below. They assume the \fBASCII\fR character set and ignore differences in case when comparing lower and upper case characters. .SS "\fBstrncat()\fR, \fBstrlcat()\fR" .sp .LP The \fBstrncat()\fR function appends at most \fIn\fR characters of string \fIs2\fR, including the terminating null character, to the end of string \fIs1\fR. It returns a pointer to the null-terminated result. The initial character of \fIs2\fR overrides the null character at the end of \fIs1\fR. If copying takes place between objects that overlap, the behavior of \fBstrncat()\fRand \fBstrlcat()\fR is undefined. .sp .LP The \fBstrlcat()\fR function appends at most (\fIdstsize\fR-\fBstrlen\fR(\fIdst\fR)-1) characters of \fIsrc\fR to \fIdst\fR (\fIdstsize\fR being the size of the string buffer \fIdst\fR). If the string pointed to by \fIdst\fR contains a null-terminated string that fits into \fIdstsize\fR bytes when \fBstrlcat()\fR is called, the string pointed to by \fIdst\fR will be a null-terminated string that fits in \fIdstsize\fR bytes (including the terminating null character) when it completes, and the initial character of \fIsrc\fR will override the null character at the end of \fIdst\fR. If the string pointed to by \fIdst\fR is longer than \fIdstsize\fR bytes when \fBstrlcat()\fR is called, the string pointed to by \fIdst\fR will not be changed. The function returns \fBmin\fR{\fIdstsize\fR,\fBstrlen\fR(\fIdst\fR)}+\fBstrlen\fR(\fIsrc\fR). Buffer overflow can be checked as follows: .sp .in +2 .nf if (strlcat(dst, src, dstsize) >= dstsize) return \(mi1; .fi .in -2 .SS "\fBstrchr()\fR, \fBstrrchr()\fR" .sp .LP The \fBstrchr()\fR function returns a pointer to the first occurrence of \fIc\fR (converted to a \fBchar\fR) in string \fIs\fR, or a null pointer if \fIc\fR does not occur in the string. The \fBstrrchr()\fR function returns a pointer to the last occurrence of \fIc\fR. The null character terminating a string is considered to be part of the string. .SS "\fBstrcmp()\fR, \fBstrncmp()\fR" .sp .LP The \fBstrcmp()\fR function compares two strings byte-by-byte, according to the ordering of your machine's character set. The function returns an integer greater than, equal to, or less than 0, if the string pointed to by \fIs1\fR is greater than, equal to, or less than the string pointed to by \fIs2\fR respectively. The sign of a non-zero return value is determined by the sign of the difference between the values of the first pair of bytes that differ in the strings being compared. The \fBstrncmp()\fR function makes the same comparison but looks at a maximum of \fIn\fR bytes. Bytes following a null byte are not compared. .SS "\fBstrcpy()\fR, \fBstrncpy()\fR, \fBstrlcpy()\fR" .sp .LP The \fBstrcpy()\fR function copies string \fIs2\fR to \fIs1\fR, including the terminating null character, stopping after the null character has been copied. The \fBstrncpy()\fR function copies exactly \fIn\fR bytes, truncating \fIs2\fR or adding null characters to \fIs1\fR if necessary. The result will not be null-terminated if the length of \fIs2\fR is \fIn\fR or more. Each function returns \fIs1\fR. If copying takes place between objects that overlap, the behavior of \fBstrcpy()\fR, \fBstrncpy()\fR, and \fBstrlcpy()\fR is undefined. .sp .LP The \fBstrlcpy()\fR function copies at most \fIdstsize\fR\(mi1 characters (\fIdstsize\fR being the size of the string buffer \fIdst\fR) from \fIsrc\fR to \fIdst\fR, truncating \fIsrc\fR if necessary. The result is always null-terminated. The function returns \fBstrlen\fR(\fIsrc\fR). Buffer overflow can be checked as follows: .sp .in +2 .nf if (strlcpy(dst, src, dstsize) >= dstsize) return \(mi1; .fi .in -2 .SS "\fBstrfree()\fR" .sp .LP The \fBstrfree()\fR function frees the memory associated with the string pointed to by \fIs\fR. This memory pointed to by \fIs\fR must be of size \fBstrlen\fR(\fIs\fR)+1, and must have been allocated (either directly or indirectly) by \fBkmem_alloc\fR(9F) or \fBkmem_zalloc\fR(9F). .SS "\fBstrspn()\fR" .sp .LP The \fBstrspn()\fR function returns the length of the initial segment of string \fIs1\fR that consists entirely of characters from string \fIs2\fR. .SS "\fBstrdup()\fR, \fBddi_strdup()\fR" .sp .LP The \fBddi_strdup()\fR function returns a pointer to a new string that is a duplicate of the string pointed to by \fIs1\fR. The returned pointer can be passed to \fBstrfree()\fR or \fBkmem_free\fR(9F). The space for the new string is obtained using \fBkmem_alloc()\fR. flag can be either \fBKM_SLEEP\fR or \fBKM_NOSLEEP\fR, and determines whether the caller can sleep for memory. \fBKM_SLEEP\fR allocations may sleep but are guaranteed to succeed. \fBKM_NOSLEEP\fR allocations are guaranteed not to sleep but may fail (return \fINULL\fR) if no memory is currently available. .sp .LP The \fBstrdup()\fR function behaves the same as the \fBddi_strdup()\fR when called with the \fBKM_SLEEP\fR flag. This means that \fBstrdup()\fR can sleep until memory is available and will always succeed. .SS "\fBstrlen()\fR, \fBstrnlen()\fR" .sp .LP The \fBstrlen()\fR function returns the number of bytes in \fIs\fR, not including the terminating null character. .sp .LP The \fBstrnlen()\fR function returns the smaller of \fIn\fR or the number of bytes in \fIs\fR, not including the terminating null character. The \fBstrnlen()\fR function never examines more than \fIn\fR bytes of the string pointed to by \fIs\fR. .SH CONTEXT .sp .LP The \fBstrdup()\fR and \fBddi_strdup()\fR functions can be called from user or kernel context. .sp .LP The \fBddi_strdup()\fR function can be called from interrupt context only if the \fBKM_NOSLEEP\fR flag is set. .sp .LP All the other string manipulation functions can be called from user, interrupt, or kernel context. .SH ATTRIBUTES .sp .LP See \fBattributes\fR(5) for descriptions of the following attributes: .sp .sp .TS tab() box; cw(2.75i) |cw(2.75i) lw(2.75i) |lw(2.75i) . ATTRIBUTE TYPEATTRIBUTE VALUE _ Interface StabilityCommitted .TE .SH SEE ALSO .sp .LP \fBstring\fR(3C), \fBattributes\fR(5), \fBbcopy\fR(9F), \fBddi_copyin\fR(9F), \fBkmem_alloc\fR(9F) .sp .LP \fIWriting Device Drivers\fR .SH NOTES .sp .LP If copying takes place between objects that overlap, the behavior of \fBstrlcat()\fR, \fBstrncat()\fR, \fBstrcpy()\fR, \fBstrlcpy()\fR, and \fBstrncpy()\fR is undefined.