diff --git a/src/header/limits/mod.rs b/src/header/limits/mod.rs
index cde6c86caf..78267ca3f3 100644
--- a/src/header/limits/mod.rs
+++ b/src/header/limits/mod.rs
@@ -1,6 +1,8 @@
 //! limits.h implementation for relibc
 //! Following https://pubs.opengroup.org/onlinepubs/7908799/xsh/limits.h.html
 
+use core::ffi::c_long;
+
 pub const HOST_NAME_MAX: usize = 64;
 pub const NAME_MAX: usize = 255;
 pub const PASS_MAX: usize = 128;
@@ -13,44 +15,56 @@ pub const NGROUPS_MAX: usize = 65536;
 pub const PAGE_SIZE: usize = 4096;
 
 // These POSIX symbols must have these values regardless of OS
-pub const _POSIX_AIO_LISTIO_MAX: usize = 2;
-pub const _POSIX_AIO_MAX: usize = 1;
-pub const _POSIX_ARG_MAX: usize = 4096;
-pub const _POSIX_CHILD_MAX: usize = 25;
-pub const _POSIX_CLOCKRES_MIN: usize = 20000000;
-pub const _POSIX_DELAYTIMER_MAX: usize = 32;
-pub const _POSIX_HOST_NAME_MAX: usize = 255;
-pub const _POSIX_LINK_MAX: usize = 8;
-pub const _POSIX_LOGIN_NAME_MAX: usize = 9;
-pub const _POSIX_MAX_CANON: usize = 255;
-pub const _POSIX_MAX_INPUT: usize = 255;
-pub const _POSIX_NAME_MAX: usize = 14;
-pub const _POSIX_NGROUPS_MAX: usize = 8;
-pub const _POSIX_OPEN_MAX: usize = 20;
-pub const _POSIX_PATH_MAX: usize = 256;
-pub const _POSIX_PIPE_BUF: usize = 512;
-pub const _POSIX_RE_DUP_MAX: usize = 255;
-pub const _POSIX_RTSIG_MAX: usize = 8;
-pub const _POSIX_SEM_NSEMS_MAX: usize = 256;
-pub const _POSIX_SEM_VALUE_MAX: usize = 32767;
-pub const _POSIX_SIGQUEUE_MAX: usize = 32;
-pub const _POSIX_SSIZE_MAX: usize = 32767;
-pub const _POSIX_STREAM_MAX: usize = 8;
-pub const _POSIX_SYMLINK_MAX: usize = 255;
-pub const _POSIX_SYMLOOP_MAX: usize = 8;
-pub const _POSIX_THREAD_DESTRUCTOR_ITERATIONS: usize = 4;
-pub const _POSIX_THREAD_KEYS_MAX: usize = 128;
-pub const _POSIX_THREAD_THREADS_MAX: usize = 64;
-pub const _POSIX_TIMER_MAX: usize = 32;
-pub const _POSIX_TTY_NAME_MAX: usize = 9;
-pub const _POSIX_TZNAME_MAX: usize = 6;
+pub const _POSIX_AIO_LISTIO_MAX: c_long = 2;
+pub const _POSIX_AIO_MAX: c_long = 1;
+pub const _POSIX_ARG_MAX: c_long = 4096;
+pub const _POSIX_CHILD_MAX: c_long = 25;
+pub const _POSIX_CLOCKRES_MIN: c_long = 20000000;
+pub const _POSIX_DELAYTIMER_MAX: c_long = 32;
+pub const _POSIX_HOST_NAME_MAX: c_long = 255;
+pub const _POSIX_LINK_MAX: c_long = 8;
+pub const _POSIX_LOGIN_NAME_MAX: c_long = 9;
+pub const _POSIX_MAX_CANON: c_long = 255;
+pub const _POSIX_MAX_INPUT: c_long = 255;
+pub const _POSIX_NAME_MAX: c_long = 14;
+pub const _POSIX_NGROUPS_MAX: c_long = 8;
+pub const _POSIX_OPEN_MAX: c_long = 20;
+pub const _POSIX_PATH_MAX: c_long = 256;
+pub const _POSIX_PIPE_BUF: c_long = 512;
+pub const _POSIX_RE_DUP_MAX: c_long = 255;
+pub const _POSIX_RTSIG_MAX: c_long = 8;
+pub const _POSIX_SEM_NSEMS_MAX: c_long = 256;
+pub const _POSIX_SEM_VALUE_MAX: c_long = 32767;
+pub const _POSIX_SIGQUEUE_MAX: c_long = 32;
+pub const _POSIX_SSIZE_MAX: c_long = 32767;
+pub const _POSIX_STREAM_MAX: c_long = 8;
+pub const _POSIX_SYMLINK_MAX: c_long = 255;
+pub const _POSIX_SYMLOOP_MAX: c_long = 8;
+pub const _POSIX_THREAD_DESTRUCTOR_ITERATIONS: c_long = 4;
+pub const _POSIX_THREAD_KEYS_MAX: c_long = 128;
+pub const _POSIX_THREAD_THREADS_MAX: c_long = 64;
+pub const _POSIX_TIMER_MAX: c_long = 32;
+pub const _POSIX_TTY_NAME_MAX: c_long = 9;
+pub const _POSIX_TZNAME_MAX: c_long = 6;
 
-pub const _POSIX2_BC_BASE_MAX: usize = 99;
-pub const _POSIX2_BC_DIM_MAX: usize = 2048;
-pub const _POSIX2_BC_SCALE_MAX: usize = 99;
-pub const _POSIX2_BC_STRING_MAX: usize = 1000;
-pub const _POSIX2_CHARCLASS_NAME_MAX: usize = 14;
-pub const _POSIX2_COLL_WEIGHTS_MAX: usize = 2;
-pub const _POSIX2_EXPR_NEST_MAX: usize = 32;
-pub const _POSIX2_LINE_MAX: usize = 2048;
-pub const _POSIX2_RE_DUP_MAX: usize = 255;
+pub const _POSIX2_BC_BASE_MAX: c_long = 99;
+pub const _POSIX2_BC_DIM_MAX: c_long = 2048;
+pub const _POSIX2_BC_SCALE_MAX: c_long = 99;
+pub const _POSIX2_BC_STRING_MAX: c_long = 1000;
+pub const _POSIX2_CHARCLASS_NAME_MAX: c_long = 14;
+pub const _POSIX2_COLL_WEIGHTS_MAX: c_long = 2;
+pub const _POSIX2_EXPR_NEST_MAX: c_long = 32;
+pub const _POSIX2_LINE_MAX: c_long = 2048;
+pub const _POSIX2_RE_DUP_MAX: c_long = 255;
+
+// These symbols must be at least the POSIX values, and sysconf will return the actual value between
+// the posix minimum and this maximum.
+pub const BC_BASE_MAX: c_long = _POSIX2_BC_BASE_MAX;
+pub const BC_DIM_MAX: c_long = _POSIX2_BC_DIM_MAX;
+pub const BC_SCALE_MAX: c_long = _POSIX2_BC_SCALE_MAX;
+pub const BC_STRING_MAX: c_long = _POSIX2_BC_STRING_MAX;
+pub const CHARCLASS_NAME_MAX: c_long = _POSIX2_CHARCLASS_NAME_MAX;
+pub const COLL_WEIGHTS_MAX: c_long = _POSIX2_COLL_WEIGHTS_MAX;
+pub const EXPR_NEST_MAX: c_long = _POSIX2_EXPR_NEST_MAX;
+pub const LINE_MAX: c_long = _POSIX2_LINE_MAX;
+pub const RE_DUP_MAX: c_long = _POSIX2_RE_DUP_MAX;
\ No newline at end of file
diff --git a/src/header/unistd/sysconf/linux.rs b/src/header/unistd/sysconf/linux.rs
index 2434e8c429..f98fc465fc 100644
--- a/src/header/unistd/sysconf/linux.rs
+++ b/src/header/unistd/sysconf/linux.rs
@@ -8,21 +8,12 @@ use core::{
 use crate::{
     header::{
         errno,
-        limits::{HOST_NAME_MAX, PAGE_SIZE},
+        limits::*,
         signal,
     },
     platform,
 };
 
-pub const _POSIX2_BC_BASE_MAX: c_long = 99;
-pub const _POSIX2_BC_DIM_MAX: c_long = 2048;
-pub const _POSIX2_BC_SCALE_MAX: c_long = 99;
-pub const _POSIX2_BC_STRING_MAX: c_long = 1000;
-pub const _POSIX2_CHARCLASS_NAME_MAX: c_long = 14;
-pub const _POSIX2_COLL_WEIGHTS_MAX: c_long = 2;
-pub const _POSIX2_EXPR_NEST_MAX: c_long = 32;
-pub const _POSIX2_LINE_MAX: c_long = 2048;
-pub const _POSIX2_RE_DUP_MAX: c_long = 255;
 pub const _XOPEN_IOV_MAX: c_long = 16;
 pub const _XOPEN_NAME_MAX: c_long = 255;
 pub const _XOPEN_PATH_MAX: c_long = 1024;
@@ -182,7 +173,7 @@ pub(super) fn sysconf_impl(name: c_int) -> c_long {
         _SC_CLK_TCK => 100,
         // TODO: getrlimit
         _SC_CHILD_MAX => -1,
-        _SC_NGROUPS_MAX => 32,
+        _SC_NGROUPS_MAX => NGROUPS_MAX as c_long,
         // TODO: getrlimit
         _SC_OPEN_MAX => -1,
         _SC_STREAM_MAX => -1,
@@ -223,14 +214,14 @@ pub(super) fn sysconf_impl(name: c_int) -> c_long {
         _SC_SEM_VALUE_MAX => -1,
         _SC_SIGQUEUE_MAX => -1,
         _SC_TIMER_MAX => -1,
-        _SC_BC_BASE_MAX => _POSIX2_BC_BASE_MAX,
-        _SC_BC_DIM_MAX => _POSIX2_BC_DIM_MAX,
-        _SC_BC_SCALE_MAX => _POSIX2_BC_SCALE_MAX,
-        _SC_BC_STRING_MAX => _POSIX2_BC_STRING_MAX,
-        _SC_COLL_WEIGHTS_MAX => _POSIX2_COLL_WEIGHTS_MAX,
-        _SC_EXPR_NEST_MAX => -1,
-        _SC_LINE_MAX => -1,
-        _SC_RE_DUP_MAX => _POSIX2_RE_DUP_MAX,
+        _SC_BC_BASE_MAX => BC_BASE_MAX,
+        _SC_BC_DIM_MAX => BC_DIM_MAX,
+        _SC_BC_SCALE_MAX => BC_SCALE_MAX,
+        _SC_BC_STRING_MAX => BC_STRING_MAX,
+        _SC_COLL_WEIGHTS_MAX => COLL_WEIGHTS_MAX,
+        _SC_EXPR_NEST_MAX => EXPR_NEST_MAX,
+        _SC_LINE_MAX => LINE_MAX,
+        _SC_RE_DUP_MAX => RE_DUP_MAX,
         _SC_2_VERSION => _POSIX_VERSION,
         _SC_2_C_BIND => _POSIX_VERSION,
         _SC_2_C_DEV => -1,