libc {
  GLIBC_2.0 {
    # functions with required interface outside normal name space
    __argz_count; __argz_stringify; __argz_next;

    # functions used in inline functions or macros
    __bzero; __strtok_r;

    # functions used in other libraries
    __stpncpy; __stpcpy; __strdup; __mempcpy; __strcasecmp; __strerror_r;
    __ffs;

    # a*
    argz_add; argz_add_sep; argz_append; argz_count; argz_create;
    argz_create_sep; argz_delete; argz_extract; argz_insert; argz_next;
    argz_replace; argz_stringify;

    # b*
    basename; bcmp; bcopy; bzero;

    # e*
    envz_add; envz_entry; envz_get; envz_merge; envz_remove;
    envz_strip;

    # f*
    ffs;

    # i*
    index;

    # m*
    memccpy; memchr; memcmp; memcpy; memfrob; memmem; memmove; memset;

    # r*
    rindex;

    # s*
    stpcpy; stpncpy; strcasecmp; strcat; strchr; strcmp; strcoll; strcpy;
    strcspn; strdup; strerror; strerror_r; strfry; strlen; strncasecmp;
    strncat; strncmp; strncpy; strndup; strnlen; strpbrk; strrchr; strsep;
    strsignal; strspn; strstr; strtok; strtok_r; strxfrm; swab;
  }
  GLIBC_2.1 {
    # functions used in macros and other libraries
    __rawmemchr; __strcasestr;

    # f*
    ffsl; ffsll;

    # m*
    mempcpy;

    # r*
    rawmemchr;

    # s*
    strcasestr; strverscmp;
  }
  GLIBC_2.1.1 {
    # extern inline functions used by <bits/string2.h>
    __mempcpy_small; __stpcpy_small; __strcspn_c1; __strcspn_c2; __strcspn_c3;
    __strcpy_small; __strspn_c1; __strspn_c2; __strspn_c3; __strpbrk_c2;
    __strpbrk_c3; __strsep_1c; __strsep_2c; __strsep_3c; __strsep_g;
    __strtok_r_1c;

    # s*
    strchrnul; __strverscmp;
  }
  GLIBC_2.2 {
    # functions used in macros.
    __strndup;

    # m*
    memrchr;
  }
  GLIBC_2.3.4 {
    # x*
    __xpg_strerror_r;
  }
  GLIBC_2.6 {
    strerror_l;
  }
}