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                                                               string(3c)



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        strcat, strncat, strcmp, strncmp, strcpy, strncpy, strlen,
        strchr, strrchr, strpbrk, strspn, strcspn, strtok
        string operations
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        SYNTAX

        #include <string.h>

        char *strcat (s1, s2)
        char *s1, *s2;

        char *strncat (s1, s2, n)
        char *s1, *s2;
        int n;

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

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

        char *strcpy (s1, s2)
        char *s1, *s2;

        char *strncpy (s1, s2, n)
        char *s1, *s2;
        int n;

        int strlen (s)
        char *s;

        char *strchr (s, c)
        char *s;
        int c;

        char *strrchr (s, c)
        char *s;
        int c;

        char *strpbrk (s1, s2)
        char *s1, *s2;

        int strspn (s1, s2)
        char *s1, *s2;

        int strcspn (s1, s2)
        char *s1, *s2;



        DG/UX 4.00                                                 Page 1
               Licensed material--property of copyright holder(s)

                                                               string(3c)



        char *strtok (s1, s2)
        char *s1, *s2;


        DESCRIPTION

        The arguments s1, s2 and s point to strings (arrays of characters
        terminated by a null character).  The functions strcat, strncat,
        strcpy, and strncpy all alter s1.  These functions do not check
        for overflow of the array pointed to by s1.

        Strcat appends a copy of string s2 to the end of string s1.
        Strncat appends at most n characters.  Each returns a pointer to
        the null-terminated result.

        Strcmp compares its arguments and returns an integer less than,
        equal to, or greater than 0, according to whether s1 is
        lexicographically less than, equal to, or greater than s2.
        Strncmp makes the same comparison but looks at at most n
        characters.

        Strcpy copies string s2 to s1, stopping after the null character
        has been copied.  Strncpy copies exactly n characters, 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.

        Strlen returns the number of characters in s, not including the
        terminating null character.

        Strchr (strrchr) returns a pointer to the first (last) occurrence
        of character c in string s, or a NULL pointer if c is not in the
        string.  The null character terminating a string is considered to
        be part of the string.

        Strpbrk returns a pointer to the first occurrence in string s1 of
        any character from string s2, or a NULL pointer if no character
        from s2 exists in s1.

        Strspn (strcspn) returns the length of the initial segment of
        string s1, which consists entirely of characters from (not from)
        string s2.

        Strtok considers the string s1 to consist of a sequence of zero
        or more text tokens separated by spans of one or more characters
        from the separator string s2.  The first call (with pointer s1
        specified) returns a pointer to the first character of the first
        token, and will have written a null character into s1 immediately
        following the returned token. The function keeps track of its
        position in the string between separate calls, so that subsequent
        calls (which must be made with the first argument a NULL pointer)



        DG/UX 4.00                                                 Page 2
               Licensed material--property of copyright holder(s)

                                                               string(3c)



        will work through the string s1 immediately following that token.

        In this way, subsequent calls will work through the string s1
        until no tokens remain.  The separator string s2 may be different
        from call to call.  When no token remains in s1, a NULL pointer
        is returned.


        NOTE

        All these functions are declared in the optional <string.h>
        header file.


        BUGS

        Strcmp and strncmp use native character comparison, which is
        signed on Data General MV-series, DEC PDP-11, and DEC VAX-11
        machines; it is unsigned on other machines.  Thus, the sign of
        the value returned when one of the characters has its high-order
        bit set is implementation-dependent.

        Character movement is performed differently in different
        implementations.  Thus overlapping moves may yield surprises.






























        DG/UX 4.00                                                 Page 3
               Licensed material--property of copyright holder(s)