diff options
Diffstat (limited to 'manual/string.texi')
| -rw-r--r-- | manual/string.texi | 33 |
1 files changed, 14 insertions, 19 deletions
diff --git a/manual/string.texi b/manual/string.texi index c98840e326..6dcd4aff44 100644 --- a/manual/string.texi +++ b/manual/string.texi @@ -2062,7 +2062,7 @@ separately. The function is not locale-dependent. @comment wchar.h @comment ISO -@deftypefun {wchar_t *} wcstok (wchar_t *@var{newstring}, const wchar_t *@var{delimiters}) +@deftypefun {wchar_t *} wcstok (wchar_t *@var{newstring}, const wchar_t *@var{delimiters}, wchar_t **@var{save_ptr}) @safety{@prelim{}@mtsafe{}@assafe{}@acsafe{}} A string can be split into tokens by making a series of calls to the function @code{wcstok}. @@ -2071,11 +2071,8 @@ The string to be split up is passed as the @var{newstring} argument on the first call only. The @code{wcstok} function uses this to set up some internal state information. Subsequent calls to get additional tokens from the same wide character string are indicated by passing a -null pointer as the @var{newstring} argument. Calling @code{wcstok} -with another non-null @var{newstring} argument reinitializes the state -information. It is guaranteed that no other library function ever calls -@code{wcstok} behind your back (which would mess up this internal state -information). +null pointer as the @var{newstring} argument, which causes the pointer +previously stored in @var{save_ptr} to be used instead. The @var{delimiters} argument is a wide character string that specifies a set of delimiters that may surround the token being extracted. All @@ -2084,8 +2081,10 @@ The first wide character that is @emph{not} a member of this set of delimiters marks the beginning of the next token. The end of the token is found by looking for the next wide character that is a member of the delimiter set. This wide character in the original wide character -string @var{newstring} is overwritten by a null wide character, and the -pointer to the beginning of the token in @var{newstring} is returned. +string @var{newstring} is overwritten by a null wide character, the +pointer past the overwritten wide character is saved in @var{save_ptr}, +and the pointer to the beginning of the token in @var{newstring} is +returned. On the next call to @code{wcstok}, the searching begins at the next wide character beyond the one that marked the end of the previous token. @@ -2095,11 +2094,6 @@ same on every call in a series of calls to @code{wcstok}. If the end of the wide character string @var{newstring} is reached, or if the remainder of string consists only of delimiter wide characters, @code{wcstok} returns a null pointer. - -Note that ``character'' is here used in the sense of byte. In a string -using a multibyte character encoding (abstract) character consisting of -more than one byte are not treated as an entity. Each byte is treated -separately. The function is not locale-dependent. @end deftypefun @strong{Warning:} Since @code{strtok} and @code{wcstok} alter the string @@ -2124,7 +2118,7 @@ does not have as its purpose the modification of a certain data structure, then it is error-prone to modify the data structure temporarily. -The functions @code{strtok} and @code{wcstok} are not reentrant. +The function @code{strtok} is not reentrant, whereas @code{wcstok} is. @xref{Nonreentrancy}, for a discussion of where and why reentrancy is important. @@ -2163,11 +2157,12 @@ available for multibyte character strings. @safety{@prelim{}@mtsafe{}@assafe{}@acsafe{}} Just like @code{strtok}, this function splits the string into several tokens which can be accessed by successive calls to @code{strtok_r}. -The difference is that the information about the next token is stored in -the space pointed to by the third argument, @var{save_ptr}, which is a -pointer to a string pointer. Calling @code{strtok_r} with a null -pointer for @var{newstring} and leaving @var{save_ptr} between the calls -unchanged does the job without hindering reentrancy. +The difference is that, as in @code{wcstok}, the information about the +next token is stored in the space pointed to by the third argument, +@var{save_ptr}, which is a pointer to a string pointer. Calling +@code{strtok_r} with a null pointer for @var{newstring} and leaving +@var{save_ptr} between the calls unchanged does the job without +hindering reentrancy. This function is defined in POSIX.1 and can be found on many systems which support multi-threading. |