Manual Pages for UNIX Operating System command usage for man strfree

Kernel Functions for Drivers                           string(9F)



NAME
     string, strcasecmp, strncasecmp, strncat,  strlcat,  strchr,
     strrchr, strcmp, strncmp, strcpy, strncpy, strlcpy, strfree,
     strspn, strdup, ddi_strdup, strlen, strnlen - string  opera-
     tions

SYNOPSIS
     #include 

     int strcasecmp(const char *s1, const char *s2);


     int strncasecmp(const char *s1, const char *s2, size_t n);


     char *strncat(char * s1, const char * s2, size_t n);


     size_t strlcat(char *dst, const char *src, size_t dstsize);


     char *strchr(const char *str, int chr);


     char *strrchr(const char *str, int chr);


     int strcmp(const char *s1, const char *s2);


     int strncmp(const char *s1, const char *s2, size_t n);


     char *strcpy(char * dst, const char * src);


     char *strncpy(char * dst, const char * src, size_t n);


     size_t strlcpy(char *dst, const char *src, size_t dstsize);


     void strfree(char *s);


     size_t strspn(const char *s1, const char *s2);


     char *strdup(const char *s1);






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Kernel Functions for Drivers                           string(9F)



     char *ddi_strdup(const char *s1, int flag);


     size_t strlen(const char *s);


     size_t strnlen(const char *s, size_t n);


INTERFACE LEVEL
     Solaris DDI specific (Solaris DDI).

DESCRIPTION
     The arguments s, s1, and s2  point  to  strings  (arrays  of
     characters  terminated  by  a null character). The strcat(),
     strncat(), strlcat(), strcpy(),  strncpy(),  strlcpy(),  and
     strfree()  functions  all  alter their first argument. Addi-
     tionally, the strcpy() function does not check for  overflow
     of the array.

  strcasecmp(), strncasecmp()
     The  strcasecmp()  and  strncasecmp()  functions  are  case-
     insensitive  versions  of   strcmp()  and  strncmp() respec-
     tively, described below.  They assume  the  ASCII  character
     set  and ignore differences in case when comparing lower and
     upper case characters.

  strncat(), strlcat()
     The strncat() function  appends  at  most  n  characters  of
     string  s2, including the terminating null character, to the
     end of  string  s1.  It  returns  a  pointer  to  the  null-
     terminated  result.  The  initial character of  s2 overrides
     the null character at the end of s1. If copying takes  place
     between  objects  that overlap, the behavior of strncat()and
     strlcat() is undefined.


     The  strlcat()  function   appends    at   most    (dstsize-
     strlen(dst)-1)  characters  of src to dst (dstsize being the
     size of the  string buffer dst). If the string pointed to by
     dst contains a null-terminated string that fits into dstsize
     bytes when strlcat() is called, the string pointed to by dst
     will  be a null-terminated string that fits in dstsize bytes
     (including the terminating  null  character)  when  it  com-
     pletes,  and  the initial character of src will override the
     null character at  the end of dst. If the string pointed  to
     by  dst  is  longer  than  dstsize  bytes  when strlcat() is
     called, the string pointed to by dst will  not  be  changed.
     The  function  returns min{dstsize,strlen(dst)}+strlen(src).
     Buffer overflow can be checked as  follows:

       if (strlcat(dst, src, dstsize) >= dstsize)



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Kernel Functions for Drivers                           string(9F)



               return -1;


  strchr(), strrchr()
     The  strchr()  function  returns  a  pointer  to  the  first
     occurrence  of  c  (converted  to a  char) in string s, or a
     null pointer  if  c  does  not  occur  in  the  string.  The
     strrchr()  function returns a pointer to the last occurrence
     of c. The null character terminating a string is  considered
     to be part of the string.

  strcmp(), strncmp()
     The strcmp() 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 s1 is greater
     than, equal to, or less than the string  pointed  to  by  s2
     respectively.  The sign of a non-zero return value is deter-
     mined  by the sign of the difference between the  values  of
     the  first  pair  of  bytes that differ in the strings being
     compared. The strncmp() function makes the  same  comparison
     but  looks  at  a maximum of n bytes. Bytes following a null
     byte are not compared.

  strcpy(), strncpy(), strlcpy()
     The strcpy() function copies string s2 to s1, including  the
     terminating  null character, stopping after the null charac-
     ter has been copied. The strncpy() function copies exactly n
     bytes,  truncating  s2  or  adding  null characters to s1 if
     necessary. The result will not  be  null-terminated  if  the
     length  of  s2  is  n or more. Each function returns s1.  If
     copying  takes  place  between  objects  that  overlap,  the
     behavior of strcpy(), strncpy(), and strlcpy() is undefined.


     The strlcpy() function copies  at most dstsize-1  characters
     (dstsize being the  size of the  string buffer dst) from src
     to dst,  truncating src if necessary.  The  result is always
     null-terminated.  The  function  returns strlen(src). Buffer
     overflow can be checked as  follows:

       if (strlcpy(dst, src, dstsize) >= dstsize)
               return -1;


  strfree()
     The strfree() function frees the memory associated with  the
     string pointed to by s.  This memory pointed to by s must be
     of size strlen(s)+1, and must have  been  allocated  (either
     directly     or    indirectly)    by    kmem_alloc(9F)    or
     kmem_zalloc(9F).




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Kernel Functions for Drivers                           string(9F)



  strspn()
     The strspn() function returns the length of the initial seg-
     ment  of string s1 that consists entirely of characters from
     string s2.

  strdup(), ddi_strdup()
     The ddi_strdup() function returns a pointer to a new  string
     that  is  a  duplicate  of  the string pointed to by s1. The
     returned   pointer   can   be   passed   to   strfree()   or
     kmem_free(9F).  The  space  for  the  new string is obtained
     using  kmem_alloc().  flag  can  be   either   KM_SLEEP   or
     KM_NOSLEEP,  and determines whether the caller can sleep for
     memory. KM_SLEEP allocations may sleep but are guaranteed to
     succeed.  KM_NOSLEEP allocations are guaranteed not to sleep
     but may fail (return NULL) if no memory is currently  avail-
     able.


     The strdup() function behaves the same as  the  ddi_strdup()
     when called with the KM_SLEEP flag. This means that strdup()
     can sleep until memory is available and will always succeed.

  strlen(), strnlen()
     The strlen() function returns the number of bytes in s,  not
     including the terminating null character.


     The strnlen() function returns  the  smaller  of  n  or  the
     number  of  bytes  in  s, not including the terminating null
     character. The strnlen() function never examines more than n
     bytes of the string pointed to by s.

CONTEXT
     The strdup() and ddi_strdup() functions can be  called  from
     user or kernel context.


     The ddi_strdup() function can be called from interrupt  con-
     text only if the KM_NOSLEEP flag is set.


     All the other string manipulation functions  can  be  called
     from user, interrupt, or kernel context.

ATTRIBUTES
     See attributes(5) for descriptions of the  following  attri-
     butes:








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Kernel Functions for Drivers                           string(9F)



     ____________________________________________________________
    |       ATTRIBUTE TYPE        |       ATTRIBUTE VALUE       |
    |_____________________________|_____________________________|
    | Interface Stability         | Committed                   |
    |_____________________________|_____________________________|


SEE ALSO
     string(3C),   attributes(5),   bcopy(9F),    ddi_copyin(9F),
     kmem_alloc(9F)


     Writing Device Drivers

NOTES
     If copying takes place between  objects  that  overlap,  the
     behavior  of  strlcat(), strncat(), strcpy(), strlcpy(), and
     strncpy() is undefined.





































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