stpncpy(3) — Linux manual page

stpncpy(3)               Library Functions Manual              stpncpy(3)

NAME         top

       stpncpy - nonstring return‐offset‐pointer copy

LIBRARY         top

       Standard C library (libc, -lc)

SYNOPSIS         top

       #include <string.h>  // see memory.h(3head)

       char *stpncpy(size_t dsize;
                     char dst[restrict dsize], const char *restrict src,
                     size_t dsize);

   Feature Test Macro Requirements for glibc (see
   feature_test_macros(7)):

       stpncpy():
           Since glibc 2.10:
               _POSIX_C_SOURCE >= 200809L
           Before glibc 2.10:
               _GNU_SOURCE

DESCRIPTION         top

       This function is equivalent to strncpy(3), but it returns a
       pointer to one past the last nonnull written character.

       It is equivalent to

           memset(mempcpy(dst, src, strnlen(src, dsize)), '\0',
                  dsize - strnlen(src, dsize))

RETURN VALUE         top

       This function returns a pointer to one past the last non-null
       character written, that is, dest + strnlen(src, n).

ATTRIBUTES         top

       For an explanation of the terms used in this section, see
       attributes(7).
       ┌──────────────────────────────────────┬───────────────┬─────────┐
       │ Interface                            │ Attribute     │ Value   │
       ├──────────────────────────────────────┼───────────────┼─────────┤
       │ stpncpy()                            │ Thread safety │ MT-Safe │
       └──────────────────────────────────────┴───────────────┴─────────┘

STANDARDS         top

       POSIX.1-2008.

HISTORY         top

       glibc 1.07.  POSIX.1-2008.

CAVEATS         top

       See strncpy(3).

SEE ALSO         top

       memory.h(3head), string_copying(7)

COLOPHON         top

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Linux man-pages 6.19            2026-08-10                     stpncpy(3)

Pages that refer to this page: memory.h(3head),  wcpncpy(3),  signal-safety(7),  string_copying(7)

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