oracular (3) strsplit.3pub.gz

NAME

       strsplit - split string into words

SYNOPSIS

       #include <publib.h>
       int strsplit(char *src, char **words, int maxw, const char *sep);

DESCRIPTION

       strsplit  splits  the  src  string  into  words  separated by one or more of the characters in sep (or by
       whitespace characters, as specified by isspace(3), if sep is the empty string).  Pointers  to  the  words
       are  stored  in  successive  elements  in  the array pointed to by words.  No more than maxw pointers are
       stored.  The input string is modifed by replacing the separator character following  a  word  with  '\0'.
       However, if there are more than maxw words, only maxw-1 words will be returned, and the maxwth pointer in
       the array will point to the rest of the string.  If maxw is 0, no modification is done.  This can be used
       for  counting  how  many words there are, e.g., so that space for the word pointer table can be allocated
       dynamically.

       strsplit splits the src string into words separated by one or more  of  the  characters  in  sep  (or  by
       whitespace characters, as defined by isspace(3), if sep is the empty string).  The src string is modified
       by replacing the separator character after each word with '\0'.  A pointer to each word  is  stored  into
       successive  elements  of  the array words.  If there are more than maxw words, a '\0' is stored after the
       first maxw-1 words only, and the words[maxw-1] will contain a pointer to the rest of the string after the
       word in words[maxw-2].

RETURN VALUE

       strsplit returns the total number of words in the input string.

EXAMPLE

       Assuming  that  words are separated by white space, to count the number of words on a line, one might say
       the following.

            n = strsplit(line, NULL, 0, "");

       To print out the fields of a colon-separated list (such as PATH, or a
       line from /etc/passwd or /etc/group), one might do the following.

            char *fields[15];
            int i, n;

            n = strsplit(list, fields, 15, ":");
            if (n > 15)
                 n = 15;
            for (i = 0; i < n; ++i)
                 printf("field %d: %s\n", i, fields[i]);

       In real life, one would of course prefer to not restrict the number of
       fields, so one might either allocated the pointer table dynamically
       (first counting the number of words using something like the first
       example), or realize that since it is the original string that is
       being modified, one can do the following:

            char *fields[15];
            int i, n;

            do {
                 n = strsplit(list, fields, 15, ":");
                 if (n > 15)
                      n = 15;
                 for (i = 0; i < n; ++i)
                      printf("field %d: %s\n", i, fields[i]);
                 list = field[n-1] + strlen(field[n-1]);
            } while (n == 15);

SEE ALSO

       publib(3), strtok(3)

AUTHOR

       The idea for this function came from C-News source code  by  Henry  Spencer  and  Geoff  Collyer.   Their
       function is very similar, but this implementation is by Lars Wirzenius (lars.wirzenius@helsinki.fi)