strndupa(3) — Linux manual page

strndupa(3)              Library Functions Manual             strndupa(3)

NAME         top

       strndupa - nonstring duplicate-into-string using-alloca

LIBRARY         top

       Standard C library (libc, -lc)

SYNOPSIS         top

       #define _GNU_SOURCE  /* See feature_test_macros(7) */
       #include <string.h>  // see memory.h(3head)

       char *strndupa(size_t n;
                     const char strn[n], size_t n);

DESCRIPTION         top

       strndupa() is similar to strndup(3), but uses alloca(3) to
       allocate the buffer.

       It is equivalent to

           strncat(strcpy(alloca(n + 1), ""), strn, n)

RETURN VALUE         top

       On success, this macro returns a pointer to the duplicated string.

ATTRIBUTES         top

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

STANDARDS         top

       GNU.

HISTORY         top

       GNU.

SEE ALSO         top

       memory.h(3head), alloca(3), strndup(3)

COLOPHON         top

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Linux man-pages 6.19            2026-08-17                    strndupa(3)

Pages that refer to this page: memory.h(3head),  strndup(3)

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