diff --git a/examples/getcpucount.c b/examples/getcpucount.c
index 66184743a..4efb385ee 100644
--- a/examples/getcpucount.c
+++ b/examples/getcpucount.c
@@ -7,9 +7,26 @@
 │   • http://creativecommons.org/publicdomain/zero/1.0/            │
 ╚─────────────────────────────────────────────────────────────────*/
 #endif
+#include "libc/calls/calls.h"
+#include "libc/errno.h"
+#include "libc/fmt/itoa.h"
 #include "libc/intrin/kprintf.h"
 #include "libc/runtime/runtime.h"
+#include "libc/stdio/stdio.h"
+
+// this implementation uses cosmopolitan specific apis so that the
+// resulting program will be 28kb in size. the proper way to do it
+// though is use sysconf(_SC_NPROCESSORS_ONLN), which is humongous
 
 int main() {
-  kprintf("%d\n", _getcpucount());
+  int count;
+  if ((count = __get_cpu_count()) != -1) {
+    char ibuf[12];
+    FormatInt32(ibuf, count);
+    tinyprint(1, ibuf, "\n", NULL);
+    return 0;
+  } else {
+    perror("__get_cpu_count");
+    return 1;
+  }
 }
diff --git a/examples/greenbean.c b/examples/greenbean.c
index a66f84e36..fd3c44abd 100644
--- a/examples/greenbean.c
+++ b/examples/greenbean.c
@@ -298,7 +298,7 @@ int main(int argc, char *argv[]) {
             PORT);
   }
 
-  threads = argc > 1 ? atoi(argv[1]) : _getcpucount();
+  threads = argc > 1 ? atoi(argv[1]) : __get_cpu_count();
   if (!(1 <= threads && threads <= 100000)) {
     kprintf("error: invalid number of threads: %d\n", threads);
     exit(1);
diff --git a/examples/sysconf.c b/examples/sysconf.c
new file mode 100644
index 000000000..937c4b231
--- /dev/null
+++ b/examples/sysconf.c
@@ -0,0 +1,25 @@
+#if 0
+/*─────────────────────────────────────────────────────────────────╗
+│ To the extent possible under law, Justine Tunney has waived      │
+│ all copyright and related or neighboring rights to this file,    │
+│ as it is written in the following disclaimers:                   │
+│   • http://unlicense.org/                                        │
+│   • http://creativecommons.org/publicdomain/zero/1.0/            │
+╚─────────────────────────────────────────────────────────────────*/
+#endif
+#include "libc/runtime/sysconf.h"
+#include "libc/stdio/stdio.h"
+
+#define SYSCONF(NAME) printf("%s %,ld\n", #NAME, sysconf(NAME))
+
+int main(int argc, char *argv[]) {
+  SYSCONF(_SC_CLK_TCK);
+  SYSCONF(_SC_PAGESIZE);
+  SYSCONF(_SC_ARG_MAX);
+  SYSCONF(_SC_CHILD_MAX);
+  SYSCONF(_SC_OPEN_MAX);
+  SYSCONF(_SC_NPROCESSORS_CONF);
+  SYSCONF(_SC_NPROCESSORS_ONLN);
+  SYSCONF(_SC_PHYS_PAGES);
+  SYSCONF(_SC_AVPHYS_PAGES);
+}
diff --git a/libc/calls/calls.h b/libc/calls/calls.h
index fcc10416a..9fa9f03ce 100644
--- a/libc/calls/calls.h
+++ b/libc/calls/calls.h
@@ -24,6 +24,7 @@
 #define _POSIX_SEMAPHORES                 _POSIX_VERSION
 #define _POSIX_SHARED_MEMORY_OBJECTS      _POSIX_VERSION
 #define _POSIX_MEMLOCK_RANGE              _POSIX_VERSION
+#define _POSIX_SPAWN                      _POSIX_VERSION
 
 #define EOF      -1         /* end of file */
 #define WEOF     -1u        /* end of file (multibyte) */
diff --git a/libc/calls/fchmod.c b/libc/calls/fchmod.c
index 27996c8fb..092a8e57c 100644
--- a/libc/calls/fchmod.c
+++ b/libc/calls/fchmod.c
@@ -29,6 +29,6 @@
  * @see chmod()
  */
 int fchmod(int fd, uint32_t mode) {
-  /* TODO(jart): Windows */
+  // TODO(jart): Windows
   return sys_fchmod(fd, mode);
 }
diff --git a/libc/calls/fchmodat.c b/libc/calls/fchmodat.c
index 7090a9f11..8e35e5c37 100644
--- a/libc/calls/fchmodat.c
+++ b/libc/calls/fchmodat.c
@@ -24,8 +24,8 @@
 #include "libc/intrin/describeflags.internal.h"
 #include "libc/intrin/strace.internal.h"
 #include "libc/intrin/weaken.h"
-#include "libc/sysv/errfuns.h"
 #include "libc/runtime/zipos.internal.h"
+#include "libc/sysv/errfuns.h"
 
 int sys_fchmodat_linux(int, const char *, unsigned, int);
 
@@ -39,7 +39,7 @@ int sys_fchmodat_linux(int, const char *, unsigned, int);
  * @param path must exist
  * @param mode contains octal flags (base 8)
  * @param flags can have `AT_SYMLINK_NOFOLLOW`
- * @raise ENOTSUP if `dirfd` or `path` use zip file system
+ * @raise EROFS if `dirfd` or `path` use zip file system
  * @errors ENOENT, ENOTDIR, ENOSYS
  * @asyncsignalsafe
  * @see fchmod()
@@ -50,7 +50,7 @@ int fchmodat(int dirfd, const char *path, uint32_t mode, int flags) {
     rc = efault();
   } else if (_weaken(__zipos_notat) &&
              (rc = __zipos_notat(dirfd, path)) == -1) {
-    rc = enotsup();
+    rc = erofs();
   } else if (!IsWindows()) {
     if (IsLinux() && flags) {
       rc = sys_fchmodat_linux(dirfd, path, mode, flags);
diff --git a/libc/calls/fchownat.c b/libc/calls/fchownat.c
index ee9951637..e1648da42 100644
--- a/libc/calls/fchownat.c
+++ b/libc/calls/fchownat.c
@@ -23,8 +23,8 @@
 #include "libc/intrin/describeflags.internal.h"
 #include "libc/intrin/strace.internal.h"
 #include "libc/intrin/weaken.h"
-#include "libc/sysv/errfuns.h"
 #include "libc/runtime/zipos.internal.h"
+#include "libc/sysv/errfuns.h"
 
 /**
  * Changes owner and/or group of path.
@@ -34,7 +34,7 @@
  * @param gid is group id, or -1 to not change
  * @param flags can have AT_SYMLINK_NOFOLLOW, etc.
  * @return 0 on success, or -1 w/ errno
- * @raise ENOTSUP if `dirfd` or `path` use zip file system
+ * @raise EROFS if `dirfd` or `path` use zip file system
  * @see chown(), lchown() for shorthand notation
  * @see /etc/passwd for user ids
  * @see /etc/group for group ids
@@ -47,7 +47,7 @@ int fchownat(int dirfd, const char *path, uint32_t uid, uint32_t gid,
     rc = efault();
   } else if (_weaken(__zipos_notat) &&
              (rc = __zipos_notat(dirfd, path)) == -1) {
-    rc = enotsup();
+    rc = erofs();
   } else {
     rc = sys_fchownat(dirfd, path, uid, gid, flags);
   }
diff --git a/libc/calls/ftruncate.c b/libc/calls/ftruncate.c
index a8cb392fa..4f7ef83c7 100644
--- a/libc/calls/ftruncate.c
+++ b/libc/calls/ftruncate.c
@@ -53,10 +53,10 @@
  * @raise ECANCELED if thread was cancelled in masked mode
  * @raise EIO if a low-level i/o error happened
  * @raise EFBIG or EINVAL if `length` is too huge
- * @raise ENOTSUP if `fd` is a zip file descriptor
  * @raise EBADF if `fd` isn't an open file descriptor
  * @raise EINVAL if `fd` is a non-file, e.g. pipe, socket
  * @raise EINVAL if `fd` wasn't opened in a writeable mode
+ * @raise EROFS if `fd` is on a read-only filesystem (e.g. zipos)
  * @raise ENOSYS on bare metal
  * @cancellationpoint
  * @asyncsignalsafe
@@ -69,7 +69,7 @@ int ftruncate(int fd, int64_t length) {
   if (fd < 0) {
     rc = ebadf();
   } else if (__isfdkind(fd, kFdZip)) {
-    rc = enotsup();
+    rc = erofs();
   } else if (IsMetal()) {
     rc = enosys();
   } else if (!IsWindows()) {
diff --git a/libc/calls/futimens.c b/libc/calls/futimens.c
index d53957468..c25e37dc8 100644
--- a/libc/calls/futimens.c
+++ b/libc/calls/futimens.c
@@ -32,10 +32,10 @@
  * @param fd is file descriptor of file whose timestamps will change
  * @param ts is {access, modified} timestamps, or null for current time
  * @return 0 on success, or -1 w/ errno
- * @raise ENOTSUP if `fd` is on the zip filesystem
  * @raise EINVAL if `flags` had an unrecognized value
  * @raise EPERM if pledge() is in play without `fattr` promise
  * @raise EINVAL if `ts` specifies a nanosecond value that's out of range
+ * @raise EROFS if `fd` is a zip file or on a read-only filesystem
  * @raise EBADF if `fd` isn't an open file descriptor
  * @raise EFAULT if `ts` memory was invalid
  * @raise ENOSYS on RHEL5 or bare metal
diff --git a/libc/calls/futimes.c b/libc/calls/futimes.c
index bb0436617..900ec18f0 100644
--- a/libc/calls/futimes.c
+++ b/libc/calls/futimes.c
@@ -30,8 +30,8 @@
  *
  * @param ts is atime/mtime, or null for current time
  * @return 0 on success, or -1 w/ errno
- * @raise ENOTSUP if `fd` is on zip filesystem
  * @raise EBADF if `fd` isn't an open file descriptor
+ * @raise EROFS if `fd` is on zip or read-only filesystem
  * @raise EPERM if pledge() is in play without `fattr` promise
  * @raise EINVAL if `tv` specifies a microsecond value that's out of range
  * @raise ENOSYS on RHEL5 or bare metal
diff --git a/libc/calls/getcpucount.c b/libc/calls/getcpucount.c
index f1433d7f8..ab846a091 100644
--- a/libc/calls/getcpucount.c
+++ b/libc/calls/getcpucount.c
@@ -19,13 +19,9 @@
 #include "libc/calls/calls.h"
 #include "libc/calls/sched-sysv.internal.h"
 #include "libc/calls/struct/cpuset.h"
-#include "libc/calls/weirdtypes.h"
+#include "libc/calls/syscall_support-nt.internal.h"
 #include "libc/dce.h"
-#include "libc/macros.internal.h"
 #include "libc/nt/accounting.h"
-#include "libc/nt/dll.h"
-#include "libc/nt/struct/systeminfo.h"
-#include "libc/nt/systeminfo.h"
 #include "libc/runtime/runtime.h"
 
 #define CTL_HW                6
@@ -34,16 +30,16 @@
 #define HW_NCPUONLINE_NETBSD  16
 #define ALL_PROCESSOR_GROUPS  0xffff
 
-static unsigned _getcpucount_linux(void) {
-  cpu_set_t s = {0};
-  if (sys_sched_getaffinity(0, sizeof(s), &s) != -1) {
-    return CPU_COUNT(&s);
+static int __get_cpu_count_linux(void) {
+  cpu_set_t cs = {0};
+  if (sys_sched_getaffinity(0, sizeof(cs), &cs) != -1) {
+    return CPU_COUNT(&cs);
   } else {
-    return 0;
+    return -1;
   }
 }
 
-static unsigned _getcpucount_bsd(void) {
+static int __get_cpu_count_bsd(void) {
   size_t n;
   int c, cmd[2];
   n = sizeof(c);
@@ -58,29 +54,19 @@ static unsigned _getcpucount_bsd(void) {
   if (!sys_sysctl(cmd, 2, &c, &n, 0, 0)) {
     return c;
   } else {
-    return 0;
+    return -1;
   }
 }
 
-static unsigned _getcpucount_impl(void) {
-  if (!IsWindows()) {
-    if (!IsBsd()) {
-      return _getcpucount_linux();
-    } else {
-      return _getcpucount_bsd();
-    }
+static textwindows int __get_cpu_count_nt(void) {
+  uint32_t res;
+  if ((res = GetMaximumProcessorCount(ALL_PROCESSOR_GROUPS))) {
+    return res;
   } else {
-    return GetMaximumProcessorCount(ALL_PROCESSOR_GROUPS);
+    return __winerr();
   }
 }
 
-static int g_cpucount;
-
-// precompute because process affinity on linux may change later
-__attribute__((__constructor__)) static void _getcpucount_init(void) {
-  g_cpucount = _getcpucount_impl();
-}
-
 /**
  * Returns number of CPUs in system.
  *
@@ -88,13 +74,20 @@ __attribute__((__constructor__)) static void _getcpucount_init(void) {
  *
  *     sysconf(_SC_NPROCESSORS_ONLN);
  *
- * Except this function isn't a bloated diamond dependency.
- *
  * On Intel systems with HyperThreading this will return the number of
- * cores multiplied by two.
+ * cores multiplied by two. On Linux, if you change cpu affinity it'll
+ * change the cpu count, which also gets inherited by child processes.
  *
- * @return cpu count or 0 if it couldn't be determined
+ * @return cpu count, or -1 w/ errno
  */
-int _getcpucount(void) {
-  return g_cpucount;
+int __get_cpu_count(void) {
+  if (!IsWindows()) {
+    if (!IsBsd()) {
+      return __get_cpu_count_linux();
+    } else {
+      return __get_cpu_count_bsd();
+    }
+  } else {
+    return __get_cpu_count_nt();
+  }
 }
diff --git a/libc/calls/getloadavg-nt.c b/libc/calls/getloadavg-nt.c
index d8325576a..65fda675a 100644
--- a/libc/calls/getloadavg-nt.c
+++ b/libc/calls/getloadavg-nt.c
@@ -60,7 +60,7 @@ static textstartup void sys_getloadavg_nt_init(void) {
   double a[3];
   if (IsWindows()) {
     load = 1;
-    cpus = _getcpucount() / 2;
+    cpus = __get_cpu_count() / 2;
     cpus = MAX(1, cpus);
     GetSystemTimes(&idle1, &kern1, &user1);
   }
diff --git a/libc/calls/getloadavg.c b/libc/calls/getloadavg.c
index 1608effd4..17f260008 100644
--- a/libc/calls/getloadavg.c
+++ b/libc/calls/getloadavg.c
@@ -18,6 +18,7 @@
 ╚─────────────────────────────────────────────────────────────────────────────*/
 #include "libc/calls/calls.h"
 #include "libc/calls/struct/sysinfo.h"
+#include "libc/calls/struct/sysinfo.internal.h"
 #include "libc/calls/syscall-nt.internal.h"
 #include "libc/dce.h"
 #include "libc/intrin/strace.internal.h"
@@ -40,7 +41,7 @@ struct loadavg {
  * @raise ENOSYS on metal
  */
 int getloadavg(double *a, int n) {
-  /* cat /proc/loadavg  */
+  // cat /proc/loadavg
   int i, rc;
   if (n > 3) n = 3;
   if (!n) {
@@ -51,7 +52,7 @@ int getloadavg(double *a, int n) {
     return sys_getloadavg_nt(a, n);
   } else if (IsLinux()) {
     struct sysinfo si;
-    if ((rc = sysinfo(&si)) != -1) {
+    if ((rc = sys_sysinfo(&si)) != -1) {
       for (i = 0; i < n; i++) {
         a[i] = 1. / 65536 * si.loads[i];
       }
diff --git a/libc/calls/getsid.c b/libc/calls/getsid.c
index 510dbce55..72f70426f 100644
--- a/libc/calls/getsid.c
+++ b/libc/calls/getsid.c
@@ -24,8 +24,7 @@
  * Creates session and sets the process group id.
  */
 int getsid(int pid) {
-  int rc;
-  rc = sys_getsid(pid);
+  int rc = sys_getsid(pid);
   STRACE("%s(%d) → %d% m", "getsid", pid, rc);
   return rc;
 }
diff --git a/libc/calls/grantpt.c b/libc/calls/grantpt.c
index c1bb1d495..b4f27f576 100644
--- a/libc/calls/grantpt.c
+++ b/libc/calls/grantpt.c
@@ -16,11 +16,14 @@
 │ TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR             │
 │ PERFORMANCE OF THIS SOFTWARE.                                                │
 ╚─────────────────────────────────────────────────────────────────────────────*/
+#include "libc/calls/internal.h"
+#include "libc/calls/struct/fd.internal.h"
 #include "libc/calls/syscall-sysv.internal.h"
 #include "libc/calls/syscall_support-sysv.internal.h"
 #include "libc/calls/termios.h"
 #include "libc/dce.h"
 #include "libc/intrin/strace.internal.h"
+#include "libc/sysv/errfuns.h"
 
 #define TIOCPTYGRANT 0x20007454
 
@@ -34,7 +37,9 @@
  */
 int grantpt(int fd) {
   int rc;
-  if (IsXnu()) {
+  if (fd < g_fds.n && g_fds.p[fd].kind == kFdZip) {
+    rc = enotty();
+  } else if (IsXnu()) {
     rc = sys_ioctl(fd, TIOCPTYGRANT);
   } else {
     rc = _isptmaster(fd);
diff --git a/libc/calls/nanos.internal.h b/libc/calls/nanos.internal.h
deleted file mode 100644
index 547557290..000000000
--- a/libc/calls/nanos.internal.h
+++ /dev/null
@@ -1,10 +0,0 @@
-#ifndef COSMOPOLITAN_LIBC_CALLS_NANOS_H_
-#define COSMOPOLITAN_LIBC_CALLS_NANOS_H_
-#if !(__ASSEMBLER__ + __LINKER__ + 0)
-COSMOPOLITAN_C_START_
-
-int128_t _nanos(int);
-
-COSMOPOLITAN_C_END_
-#endif /* !(__ASSEMBLER__ + __LINKER__ + 0) */
-#endif /* COSMOPOLITAN_LIBC_CALLS_NANOS_H_ */
diff --git a/libc/calls/pipe2.c b/libc/calls/pipe2.c
index 8b05aa0a4..2cfcc625c 100644
--- a/libc/calls/pipe2.c
+++ b/libc/calls/pipe2.c
@@ -27,6 +27,12 @@
 /**
  * Creates file-less file descriptors for interprocess communication.
  *
+ * This function offers atomic operation on all supported platforms
+ * except for XNU and RHEL5 where it's polyfilled.
+ *
+ * @params flags may contain `O_CLOEXEC`, `O_NONBLOCK`, and `O_DIRECT`
+ * @raise EINVAL if flags has invalid or unsupported bits
+ * @raise EFAULT if `pipefd` doesn't point to valid memory
  * @raise EMFILE if process `RLIMIT_NOFILE` has been reached
  * @raise ENFILE if system-wide file limit has been reached
  * @param pipefd is used to return (reader, writer) file descriptors
diff --git a/libc/calls/ptsname.c b/libc/calls/ptsname.c
index 5102b6f4a..8532af1c9 100644
--- a/libc/calls/ptsname.c
+++ b/libc/calls/ptsname.c
@@ -16,10 +16,13 @@
 │ TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR             │
 │ PERFORMANCE OF THIS SOFTWARE.                                                │
 ╚─────────────────────────────────────────────────────────────────────────────*/
+#include "libc/calls/internal.h"
+#include "libc/calls/struct/fd.internal.h"
 #include "libc/calls/syscall_support-sysv.internal.h"
 #include "libc/calls/termios.h"
 #include "libc/errno.h"
 #include "libc/intrin/strace.internal.h"
+#include "libc/sysv/errfuns.h"
 
 static char g_ptsname[16];
 
@@ -30,7 +33,10 @@ static char g_ptsname[16];
  */
 char *ptsname(int fd) {
   char *res;
-  if (!_ptsname(fd, g_ptsname, sizeof(g_ptsname))) {
+  if (fd < g_fds.n && g_fds.p[fd].kind == kFdZip) {
+    enotty();
+    res = 0;
+  } else if (!_ptsname(fd, g_ptsname, sizeof(g_ptsname))) {
     res = g_ptsname;
   } else {
     res = 0;
diff --git a/libc/calls/sysinfo.c b/libc/calls/sysinfo.c
index f0a1138d3..245dc161a 100644
--- a/libc/calls/sysinfo.c
+++ b/libc/calls/sysinfo.c
@@ -53,6 +53,8 @@ static int64_t GetPhysmem(void) {
 static int sys_sysinfo_bsd(struct sysinfo *info) {
   info->uptime = GetUptime();
   info->totalram = GetPhysmem();
+  info->bufferram = GetPhysmem();
+  info->mem_unit = 1;
   return 0;
 }
 
diff --git a/libc/calls/truncate.c b/libc/calls/truncate.c
index 796fafbfc..ebd252c2c 100644
--- a/libc/calls/truncate.c
+++ b/libc/calls/truncate.c
@@ -25,8 +25,8 @@
 #include "libc/intrin/asan.internal.h"
 #include "libc/intrin/strace.internal.h"
 #include "libc/intrin/weaken.h"
-#include "libc/sysv/errfuns.h"
 #include "libc/runtime/zipos.internal.h"
+#include "libc/sysv/errfuns.h"
 
 /**
  * Changes size of file.
@@ -50,15 +50,14 @@
  * @raise ECANCELED if thread was cancelled in masked mode
  * @raise EFBIG or EINVAL if `length` is too huge
  * @raise EFAULT if `path` points to invalid memory
- * @raise ENOTSUP if `path` is a zip filesystem path
  * @raise EACCES if we don't have permission to search a component of `path`
  * @raise ENOTDIR if a directory component in `path` exists as non-directory
  * @raise ENAMETOOLONG if symlink-resolved `path` length exceeds `PATH_MAX`
  * @raise ENAMETOOLONG if component in `path` exists longer than `NAME_MAX`
  * @raise ELOOP if a loop was detected resolving components of `path`
+ * @raise EROFS if `path` is on a read-only filesystem (e.g. zip)
  * @raise ENOENT if `path` doesn't exist or is an empty string
  * @raise ETXTBSY if `path` is an executable being executed
- * @raise EROFS if `path` is on a read-only filesystem
  * @raise ENOSYS on bare metal
  * @cancellationpoint
  * @see ftruncate()
@@ -75,7 +74,7 @@ int truncate(const char *path, int64_t length) {
     rc = efault();
   } else if (_weaken(__zipos_parseuri) &&
              _weaken(__zipos_parseuri)(path, &zipname) != -1) {
-    rc = enotsup();
+    rc = erofs();
   } else if (!IsWindows()) {
     rc = sys_truncate(path, length, length);
     if (IsNetbsd() && rc == -1 && errno == ENOSPC) {
diff --git a/libc/calls/unlockpt.c b/libc/calls/unlockpt.c
index bbeed8ddf..5d45ebe09 100644
--- a/libc/calls/unlockpt.c
+++ b/libc/calls/unlockpt.c
@@ -17,6 +17,8 @@
 │ PERFORMANCE OF THIS SOFTWARE.                                                │
 ╚─────────────────────────────────────────────────────────────────────────────*/
 #include "libc/calls/calls.h"
+#include "libc/calls/internal.h"
+#include "libc/calls/struct/fd.internal.h"
 #include "libc/calls/syscall-sysv.internal.h"
 #include "libc/calls/syscall_support-sysv.internal.h"
 #include "libc/calls/termios.h"
@@ -37,7 +39,9 @@
  */
 int unlockpt(int fd) {
   int rc, unlock = 0;
-  if (IsFreebsd() || IsOpenbsd() || IsNetbsd()) {
+  if (fd < g_fds.n && g_fds.p[fd].kind == kFdZip) {
+    rc = enotty();
+  } else if (IsFreebsd() || IsOpenbsd() || IsNetbsd()) {
     rc = _isptmaster(fd);
   } else if (IsXnu()) {
     rc = sys_ioctl(fd, TIOCPTYUNLK);
diff --git a/libc/calls/utimens.c b/libc/calls/utimens.c
index 7f00c8f54..b37c6f147 100644
--- a/libc/calls/utimens.c
+++ b/libc/calls/utimens.c
@@ -28,9 +28,9 @@
 #include "libc/intrin/describeflags.internal.h"
 #include "libc/intrin/strace.internal.h"
 #include "libc/intrin/weaken.h"
+#include "libc/runtime/zipos.internal.h"
 #include "libc/sysv/consts/at.h"
 #include "libc/sysv/errfuns.h"
-#include "libc/runtime/zipos.internal.h"
 
 int __utimens(int fd, const char *path, const struct timespec ts[2],
               int flags) {
@@ -47,7 +47,7 @@ int __utimens(int fd, const char *path, const struct timespec ts[2],
   } else if (__isfdkind(fd, kFdZip) ||
              (path && (_weaken(__zipos_parseuri) &&
                        _weaken(__zipos_parseuri)(path, &zipname) != -1))) {
-    rc = enotsup();
+    rc = erofs();
   } else if (IsLinux() && !__is_linux_2_6_23() && fd == AT_FDCWD && !flags) {
     rc = sys_utimes(path, (void *)ts);  // rhel5 truncates to seconds
   } else if (!IsWindows()) {
diff --git a/libc/calls/utimensat.c b/libc/calls/utimensat.c
index b97d3ce6e..318fe447f 100644
--- a/libc/calls/utimensat.c
+++ b/libc/calls/utimensat.c
@@ -25,9 +25,9 @@
 #include "libc/intrin/describeflags.internal.h"
 #include "libc/intrin/strace.internal.h"
 #include "libc/intrin/weaken.h"
+#include "libc/runtime/zipos.internal.h"
 #include "libc/sysv/consts/at.h"
 #include "libc/sysv/errfuns.h"
-#include "libc/runtime/zipos.internal.h"
 
 /**
  * Sets access/modified time on file, the modern way.
@@ -48,13 +48,12 @@
  * @raise EINVAL if `flags` had an unrecognized value
  * @raise EPERM if pledge() is in play without `fattr` promise
  * @raise EACCES if unveil() is in play and `path` isn't unveiled
- * @raise ENOTSUP if `path` is a zip filesystem path or `dirfd` is zip
  * @raise EINVAL if `ts` specifies a nanosecond value that's out of range
  * @raise ENAMETOOLONG if symlink-resolved `path` length exceeds `PATH_MAX`
  * @raise ENAMETOOLONG if component in `path` exists longer than `NAME_MAX`
  * @raise EBADF if `dirfd` isn't a valid fd or `AT_FDCWD`
  * @raise EFAULT if `path` or `ts` memory was invalid
- * @raise EROFS if `path` is on read-only filesystem
+ * @raise EROFS if `path` is on read-only filesystem (e.g. zipos)
  * @raise ENOSYS on bare metal or on rhel5 when `dirfd` or `flags` is used
  * @asyncsignalsafe
  * @threadsafe
diff --git a/libc/intrin/divmodti4.c b/libc/intrin/divmodti4.c
index eb572e555..465555c27 100644
--- a/libc/intrin/divmodti4.c
+++ b/libc/intrin/divmodti4.c
@@ -18,7 +18,7 @@
  * @return quotient or result of division
  * @note rounds towards zero
  */
-COMPILER_RT_ABI ti_int __divmodti4(ti_int a, ti_int b, tu_int *opt_out_rem) {
+ti_int __divmodti4(ti_int a, ti_int b, tu_int *opt_out_rem) {
   int k;
   tu_int r;
   ti_int sa, sb, sq, sr, x, y, q;
diff --git a/libc/intrin/divti3.c b/libc/intrin/divti3.c
index b2bbc7aaa..f878fab4b 100644
--- a/libc/intrin/divti3.c
+++ b/libc/intrin/divti3.c
@@ -17,6 +17,6 @@
  * @return quotient or result of division
  * @note rounds towards zero
  */
-COMPILER_RT_ABI ti_int __divti3(ti_int a, ti_int b) {
+ti_int __divti3(ti_int a, ti_int b) {
   return __divmodti4(a, b, NULL);
 }
diff --git a/libc/mem/critbit0_clear.c b/libc/mem/critbit0_clear.c
index 714dbe8ad..79e598756 100644
--- a/libc/mem/critbit0_clear.c
+++ b/libc/mem/critbit0_clear.c
@@ -26,9 +26,9 @@ static void critbit0_clear_traverse(void *top) {
     struct CritbitNode *q = (void *)(p - 1);
     critbit0_clear_traverse(q->child[0]);
     critbit0_clear_traverse(q->child[1]);
-    free(q), q = NULL;
+    free(q);
   } else {
-    free(p), p = NULL;
+    free(p);
   }
 }
 
diff --git a/libc/runtime/cocmd.c b/libc/runtime/cocmd.c
index e4e1f3ded..ca47e5282 100644
--- a/libc/runtime/cocmd.c
+++ b/libc/runtime/cocmd.c
@@ -218,64 +218,69 @@ static const char *GetOptArg(int c, int *i, int j) {
 static int Echo(void) {
   int i = 1;
   bool once = false;
-  const char *l = " ";
-  if (i < n && !strcmp(args[i], "-l")) {
-    ++i, l = "\n";
+  bool print_newline = true;
+  if (i < n && args[i][0] == '-' && args[i][1] == 'n' && !args[i][2]) {
+    ++i, print_newline = false;
   }
   for (; i < n; ++i) {
     if (once) {
-      Write(1, l);
+      Write(1, " ");
     } else {
       once = true;
     }
     Write(1, args[i]);
   }
-  Write(1, "\n");
+  if (print_newline) {
+    Write(1, "\n");
+  }
+  return 0;
+}
+
+static int CatDump(const char *path, int fd, bool dontclose) {
+  ssize_t rc;
+  char buf[512];
+  for (;;) {
+    rc = read(fd, buf, sizeof(buf));
+    if (rc == -1) {
+      perror(path);
+      if (!dontclose) {
+        close(fd);
+      }
+      return 1;
+    }
+    if (!rc) break;
+    rc = write(1, buf, rc);
+    if (rc == -1) {
+      perror("write");
+      if (!dontclose) {
+        close(fd);
+      }
+      return 1;
+    }
+  }
+  if (!dontclose && close(fd)) {
+    perror(path);
+    return 1;
+  }
   return 0;
 }
 
 static int Cat(void) {
-  int i, fd;
-  ssize_t rc;
-  char buf[512];
+  int i, fd, rc;
   if (n < 2) {
-    for (;;) {
-      rc = read(0, buf, sizeof(buf));
-      if (rc == -1) {
-        perror("read");
-        return 1;
-      }
-      if (!rc) break;
-      rc = write(1, buf, rc);
-      if (rc == -1) {
-        perror("write");
-        return 1;
-      }
-    }
+    return CatDump("<stdin>", 0, true);
   } else {
     for (i = 1; i < n; ++i) {
-      if ((fd = open(args[i], O_RDONLY)) == -1) {
+      bool dontclose = false;
+      if (args[i][0] == '-' && !args[i][1]) {
+        dontclose = true;
+        fd = 0;
+      } else if ((fd = open(args[i], O_RDONLY)) == -1) {
         perror(args[i]);
         return 1;
       }
-      for (;;) {
-        rc = read(fd, buf, sizeof(buf));
-        if (rc == -1) {
-          perror(args[i]);
-          close(fd);
-          return 1;
-        }
-        if (!rc) break;
-        rc = write(1, buf, rc);
-        if (rc == -1) {
-          perror("write");
-          close(fd);
-          return 1;
-        }
-      }
-      if (close(fd)) {
-        perror(args[i]);
-        return 1;
+      if ((rc = CatDump(args[i], fd, dontclose))) {
+        return rc;
       }
     }
   }
diff --git a/libc/runtime/getargmax.c b/libc/runtime/getargmax.c
index 25aabc1ae..7792e50f9 100644
--- a/libc/runtime/getargmax.c
+++ b/libc/runtime/getargmax.c
@@ -17,17 +17,50 @@
 │ PERFORMANCE OF THIS SOFTWARE.                                                │
 ╚─────────────────────────────────────────────────────────────────────────────*/
 #include "libc/dce.h"
+#include "libc/macros.internal.h"
 #include "libc/runtime/runtime.h"
+#include "libc/sysv/consts/limits.h"
+#include "libc/sysv/consts/rlimit.h"
+
+#define CTL_KERN    1
+#define KERN_ARGMAX 8
 
 /**
- * Returns `ARG_MAX` for host platform.
+ * Returns expensive but more correct version of `ARG_MAX`.
  */
-int __arg_max(void) {
-  if (IsWindows()) return 32767;
-  if (IsLinux()) return 128 * 1024;
-  if (IsNetbsd()) return 256 * 1024;
-  if (IsFreebsd()) return 512 * 1024;
-  if (IsOpenbsd()) return 512 * 1024;
-  if (IsXnu()) return 1024 * 1024;
-  return ARG_MAX;
+int __get_arg_max(void) {
+  if (IsLinux()) {
+    // You might think that just returning a constant 128KiB (ARG_MAX)
+    // would make sense, as this guy did:
+    //
+    //   https://lkml.org/lkml/2017/11/15/813...
+    //
+    //   I suspect a 128kB sysconf(_SC_ARG_MAX) is the sanest bet, simply
+    //   because of that "conservative is better than aggressive".
+    //
+    //   Especially since _technically_ we're still limiting things to that
+    //   128kB due to the single-string limit.
+    //
+    //                 Linus
+    //
+    // In practice that caused us trouble with toybox tests for xargs
+    // edge cases. The tests assume that they can at least reach the
+    // kernel's "minimum maximum" of 128KiB, but if we report 128KiB for
+    // _SC_ARG_MAX and xargs starts subtracting the environment space
+    // and so on from that, then xargs will think it's run out of space
+    // when given 128KiB of data, which should always work. See this
+    // thread for more:
+    //
+    // http://lists.landley.net/pipermail/toybox-landley.net/2019-November/011229.html
+    //
+    // So let's resign ourselves to tracking what the kernel actually
+    // does. Right now (2019, Linux 5.3) that amounts to:
+    uint64_t stacksz;
+    stacksz = __get_rlimit(RLIMIT_STACK);
+    return MAX(MIN(stacksz / 4, 3 * (8 * 1024 * 1024) / 4), _ARG_MAX);
+  } else if (IsBsd()) {
+    return __get_sysctl(CTL_KERN, KERN_ARGMAX);
+  } else {
+    return _ARG_MAX;
+  }
 }
diff --git a/libc/runtime/getmaxfd.c b/libc/runtime/getavphyspages.c
similarity index 81%
rename from libc/runtime/getmaxfd.c
rename to libc/runtime/getavphyspages.c
index 14f63eee4..d55407037 100644
--- a/libc/runtime/getmaxfd.c
+++ b/libc/runtime/getavphyspages.c
@@ -1,7 +1,7 @@
 /*-*- mode:c;indent-tabs-mode:nil;c-basic-offset:2;tab-width:8;coding:utf-8 -*-│
 │vi: set net ft=c ts=2 sts=2 sw=2 fenc=utf-8                                :vi│
 ╞══════════════════════════════════════════════════════════════════════════════╡
-│ Copyright 2021 Justine Alexandra Roberts Tunney                              │
+│ Copyright 2023 Justine Alexandra Roberts Tunney                              │
 │                                                                              │
 │ Permission to use, copy, modify, and/or distribute this software for         │
 │ any purpose with or without fee is hereby granted, provided that the         │
@@ -16,22 +16,11 @@
 │ TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR             │
 │ PERFORMANCE OF THIS SOFTWARE.                                                │
 ╚─────────────────────────────────────────────────────────────────────────────*/
-#include "libc/calls/syscall-sysv.internal.h"
-#include "libc/dce.h"
+#include "libc/calls/struct/sysinfo.h"
 #include "libc/runtime/runtime.h"
-#include "libc/sysv/consts/rlimit.h"
 
-#define F_MAXFD 11
-
-/**
- * Returns maximum number of open files.
- */
-long _GetMaxFd(void) {
-  int rc;
-  if (IsNetbsd()) {
-    if ((rc = __sys_fcntl(0, F_MAXFD, 0)) != -1) {
-      return rc;
-    }
-  }
-  return _GetResourceLimit(RLIMIT_NOFILE);
+long __get_avphys_pages(void) {
+  struct sysinfo si;
+  if (sysinfo(&si) == -1) return -1;
+  return (((int64_t)si.freeram + si.bufferram) * si.mem_unit) / FRAMESIZE;
 }
diff --git a/libc/runtime/getphyspages.c b/libc/runtime/getphyspages.c
new file mode 100644
index 000000000..5212ee7e3
--- /dev/null
+++ b/libc/runtime/getphyspages.c
@@ -0,0 +1,26 @@
+/*-*- mode:c;indent-tabs-mode:nil;c-basic-offset:2;tab-width:8;coding:utf-8 -*-│
+│vi: set net ft=c ts=2 sts=2 sw=2 fenc=utf-8                                :vi│
+╞══════════════════════════════════════════════════════════════════════════════╡
+│ Copyright 2023 Justine Alexandra Roberts Tunney                              │
+│                                                                              │
+│ Permission to use, copy, modify, and/or distribute this software for         │
+│ any purpose with or without fee is hereby granted, provided that the         │
+│ above copyright notice and this permission notice appear in all copies.      │
+│                                                                              │
+│ THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL                │
+│ WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED                │
+│ WARRANTIES OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE             │
+│ AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL         │
+│ DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR        │
+│ PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER               │
+│ TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR             │
+│ PERFORMANCE OF THIS SOFTWARE.                                                │
+╚─────────────────────────────────────────────────────────────────────────────*/
+#include "libc/calls/struct/sysinfo.h"
+#include "libc/runtime/runtime.h"
+
+long __get_phys_pages(void) {
+  struct sysinfo si;
+  if (sysinfo(&si) == -1) return -1;
+  return ((int64_t)si.totalram * si.mem_unit) / FRAMESIZE;
+}
diff --git a/libc/runtime/getresourcelimit.c b/libc/runtime/getresourcelimit.c
index e678149f0..3b670585a 100644
--- a/libc/runtime/getresourcelimit.c
+++ b/libc/runtime/getresourcelimit.c
@@ -21,9 +21,9 @@
 #include "libc/macros.internal.h"
 #include "libc/sysv/consts/rlim.h"
 
-long _GetResourceLimit(int resource) {
+long __get_rlimit(int resource) {
   struct rlimit rl;
-  getrlimit(resource, &rl);
+  if (getrlimit(resource, &rl) == -1) return -1;
   if (rl.rlim_cur == RLIM_INFINITY) return -1;
   return MIN(rl.rlim_cur, LONG_MAX);
 }
diff --git a/libc/calls/nanos.c b/libc/runtime/getsysctl.c
similarity index 83%
rename from libc/calls/nanos.c
rename to libc/runtime/getsysctl.c
index 14728f272..6c5fd7ecd 100644
--- a/libc/calls/nanos.c
+++ b/libc/runtime/getsysctl.c
@@ -1,7 +1,7 @@
 /*-*- mode:c;indent-tabs-mode:nil;c-basic-offset:2;tab-width:8;coding:utf-8 -*-│
 │vi: set net ft=c ts=2 sts=2 sw=2 fenc=utf-8                                :vi│
 ╞══════════════════════════════════════════════════════════════════════════════╡
-│ Copyright 2022 Justine Alexandra Roberts Tunney                              │
+│ Copyright 2023 Justine Alexandra Roberts Tunney                              │
 │                                                                              │
 │ Permission to use, copy, modify, and/or distribute this software for         │
 │ any purpose with or without fee is hereby granted, provided that the         │
@@ -17,18 +17,15 @@
 │ PERFORMANCE OF THIS SOFTWARE.                                                │
 ╚─────────────────────────────────────────────────────────────────────────────*/
 #include "libc/calls/calls.h"
-#include "libc/calls/struct/timespec.h"
-#include "libc/time/time.h"
+#include "libc/runtime/runtime.h"
 
-/**
- * Returns nanoseconds since UNIX epoch.
- */
-int128_t _nanos(int timer) {
-  int128_t nanos;
-  struct timespec ts;
-  clock_gettime(timer, &ts);
-  nanos = ts.tv_sec;
-  nanos *= 1000000000;
-  nanos += ts.tv_nsec;
-  return nanos;
+long __get_sysctl(int x, int y) {
+  int value;
+  int mib[2] = {x, y};
+  size_t len = sizeof(value);
+  if (sys_sysctl(mib, 2, &value, &len, 0, 0) != -1) {
+    return value;
+  } else {
+    return -1;
+  }
 }
diff --git a/libc/runtime/runtime.h b/libc/runtime/runtime.h
index e619bcb0e..cebe1fb5e 100644
--- a/libc/runtime/runtime.h
+++ b/libc/runtime/runtime.h
@@ -129,9 +129,14 @@ bool IsCygwin(void);
 const char *GetCpuidOs(void);
 const char *GetCpuidEmulator(void);
 void GetCpuidBrand(char[13], uint32_t);
-long _GetResourceLimit(int);
+long __get_rlimit(int);
+int __set_rlimit(int, int64_t);
 const char *__describe_os(void);
-int __arg_max(void);
+long __get_sysctl(int, int);
+int __get_arg_max(void) pureconst;
+int __get_cpu_count(void) pureconst;
+long __get_avphys_pages(void) pureconst;
+long __get_phys_pages(void) pureconst;
 #endif /* _COSMO_SOURCE */
 
 COSMOPOLITAN_C_END_
diff --git a/libc/runtime/sysconf.c b/libc/runtime/sysconf.c
index eff1f8b9f..0231d1f12 100644
--- a/libc/runtime/sysconf.c
+++ b/libc/runtime/sysconf.c
@@ -17,10 +17,21 @@
 │ PERFORMANCE OF THIS SOFTWARE.                                                │
 ╚─────────────────────────────────────────────────────────────────────────────*/
 #include "libc/runtime/sysconf.h"
+#include "libc/calls/calls.h"
+#include "libc/calls/struct/rlimit.h"
+#include "libc/calls/struct/sysinfo.h"
+#include "libc/calls/struct/sysinfo.internal.h"
+#include "libc/dce.h"
+#include "libc/limits.h"
+#include "libc/macros.internal.h"
 #include "libc/runtime/clktck.h"
 #include "libc/runtime/runtime.h"
+#include "libc/runtime/sysconf.h"
+#include "libc/sysv/consts/_posix.h"
 #include "libc/sysv/consts/limits.h"
 #include "libc/sysv/consts/rlimit.h"
+#include "libc/sysv/errfuns.h"
+#include "libc/thread/thread.h"
 
 /**
  * Returns configuration value about system.
@@ -28,30 +39,58 @@
  * The following parameters are supported:
  *
  * - `_SC_CLK_TCK` returns number of clock ticks per second
- * - `_SC_ARG_MAX` currently always returns 32768 due to Windows
+ * - `_SC_ARG_MAX` will perform expensive rlimit calculations
  * - `_SC_PAGESIZE` currently always returns 65536 due to Windows
- * - `_SC_NPROCESSORS_ONLN` returns number of CPUs in the system
- * - `_SC_OPEN_MAX` returns maximum number of open files
+ * - `_SC_AVPHYS_PAGES` returns average physical memory pages
+ * - `_SC_PHYS_PAGES` returns physical memory pages available
+ * - `_SC_NPROCESSORS_ONLN` returns number of effective CPUs
  * - `_SC_CHILD_MAX` returns maximum number of processes
+ * - `_SC_OPEN_MAX` returns maximum number of open files
  *
+ * @return value on success, or -1 w/ errno
+ * @raise EINVAL if `name` isn't valid
  */
 long sysconf(int name) {
   int n;
   switch (name) {
-    case _SC_ARG_MAX:
-      return _ARG_MAX;
-    case _SC_CHILD_MAX:
-      return _GetResourceLimit(RLIMIT_NPROC);
     case _SC_CLK_TCK:
       return CLK_TCK;
-    case _SC_OPEN_MAX:
-      return _GetMaxFd();
     case _SC_PAGESIZE:
       return FRAMESIZE;
+    case _SC_ARG_MAX:
+      return __get_arg_max();
+    case _SC_CHILD_MAX:
+      return __get_rlimit(RLIMIT_NPROC);
+    case _SC_OPEN_MAX:
+      return __get_rlimit(RLIMIT_NOFILE);
+    case _SC_NPROCESSORS_CONF:
     case _SC_NPROCESSORS_ONLN:
-      n = _getcpucount();
-      return n > 0 ? n : -1;
+      return __get_cpu_count();
+    case _SC_PHYS_PAGES:
+      return __get_phys_pages();
+    case _SC_AVPHYS_PAGES:
+      return __get_avphys_pages();
+    case _SC_THREADS:
+      return _POSIX_THREADS;
+    case _SC_THREAD_DESTRUCTOR_ITERATIONS:
+      return PTHREAD_DESTRUCTOR_ITERATIONS;
+    case _SC_THREAD_KEYS_MAX:
+      return PTHREAD_KEYS_MAX;
+    case _SC_THREAD_STACK_MIN:
+      return PTHREAD_STACK_MIN;
+    case _SC_THREAD_THREADS_MAX:
+      return LONG_MAX;
+    case _SC_LINE_MAX:
+      return _POSIX2_LINE_MAX;
+    case _SC_MONOTONIC_CLOCK:
+      return _POSIX_MONOTONIC_CLOCK;
+    case _SC_HOST_NAME_MAX:
+      return _POSIX_HOST_NAME_MAX;
+    case _SC_SPAWN:
+      return _POSIX_SPAWN;
+    case _SC_SYMLOOP_MAX:
+      return _POSIX_SYMLOOP_MAX;
     default:
-      return -1;
+      return einval();
   }
 }
diff --git a/libc/stdio/appendz.c b/libc/stdio/appendz.c
index a71a6142f..8caca7051 100644
--- a/libc/stdio/appendz.c
+++ b/libc/stdio/appendz.c
@@ -37,12 +37,10 @@ struct appendz appendz(char *p) {
     unassert(z.n >= W * 2 && !(z.n & (W - 1)));
     z.i = *(size_t *)(p + z.n - W);
     if (!IsTiny() && W == 8) {
-      /*
-       * This check should fail if an append*() function was passed a
-       * pointer that was allocated manually by malloc(). Append ptrs
-       * can be free()'d safely, but they need to be allocated by the
-       * append library, because we write a special value to the end.
-       */
+      // This check should fail if an append*() function was passed a
+      // pointer that was allocated manually by malloc(). Append ptrs
+      // can be free()'d safely, but they need to be allocated by the
+      // append library, because we write a special value to the end.
       unassert((z.i >> 48) == APPEND_COOKIE);
       z.i &= 0x0000ffffffffffff;
     }
diff --git a/libc/stdio/dirstream.c b/libc/stdio/dirstream.c
index 9f3b7a274..9437dc81a 100644
--- a/libc/stdio/dirstream.c
+++ b/libc/stdio/dirstream.c
@@ -413,24 +413,6 @@ static struct dirent *readdir_zipos(DIR *dir) {
   return ent;
 }
 
-static void *golden(void *a, const void *b, size_t n) {
-  size_t i;
-  char *volatile d = a;
-  const char *volatile s = b;
-  if (d > s) {
-    for (i = n; i--;) {
-      d[i] = s[i];
-      asm volatile("" ::: "memory");
-    }
-  } else {
-    for (i = 0; i < n; ++i) {
-      d[i] = s[i];
-      asm volatile("" ::: "memory");
-    }
-  }
-  return d;
-}
-
 static struct dirent *readdir_unix(DIR *dir) {
   if (dir->buf_pos >= dir->buf_end) {
     long basep = dir->tell;
diff --git a/libc/stdio/puts.c b/libc/stdio/puts.c
index cae291488..459332ba7 100644
--- a/libc/stdio/puts.c
+++ b/libc/stdio/puts.c
@@ -20,7 +20,7 @@
 #include "libc/stdio/stdio.h"
 #include "libc/str/str.h"
 
-static inline int PutsImpl(const char *s, FILE *f) {
+static inline int puts_unlocked(const char *s, FILE *f) {
   size_t n, r;
   if ((n = strlen(s))) {
     r = fwrite_unlocked(s, 1, n, f);
@@ -45,7 +45,7 @@ int puts(const char *s) {
   int bytes;
   f = stdout;
   flockfile(f);
-  bytes = PutsImpl(s, f);
+  bytes = puts_unlocked(s, f);
   funlockfile(f);
   return bytes;
 }
diff --git a/libc/thread/pthread_attr_init.c b/libc/thread/pthread_attr_init.c
index 231d7db1d..dbd16ab09 100644
--- a/libc/thread/pthread_attr_init.c
+++ b/libc/thread/pthread_attr_init.c
@@ -38,7 +38,7 @@
 errno_t pthread_attr_init(pthread_attr_t *attr) {
   *attr = (pthread_attr_t){
       .__stacksize = GetStackSize(),
-      .__guardsize = getauxval(AT_PAGESZ),
+      .__guardsize = GetGuardSize(),
   };
   return 0;
 }
diff --git a/net/turfwar/turfwar.c b/net/turfwar/turfwar.c
index 6a75c83a5..e81038e15 100644
--- a/net/turfwar/turfwar.c
+++ b/net/turfwar/turfwar.c
@@ -1916,7 +1916,7 @@ int main(int argc, char *argv[]) {
   // we don't have proper futexes on these platforms
   // we'll be somewhat less aggressive about workers
   if (IsXnu() || IsNetbsd()) {
-    g_workers = MIN(g_workers, _getcpucount());
+    g_workers = MIN(g_workers, (unsigned)__get_cpu_count());
   }
 
   // user interface
diff --git a/test/libc/calls/sched_getaffinity_test.c b/test/libc/calls/sched_getaffinity_test.c
index 3121048c4..6a6112ad0 100644
--- a/test/libc/calls/sched_getaffinity_test.c
+++ b/test/libc/calls/sched_getaffinity_test.c
@@ -51,7 +51,7 @@ TEST(sched_getaffinity, firstOnly) {
 }
 
 TEST(sched_getaffinity, secondOnly) {
-  if (_getcpucount() < 2) return;
+  if (__get_cpu_count() < 2) return;
   cpu_set_t x, y;
   CPU_ZERO(&x);
   CPU_SET(1, &x);
diff --git a/test/libc/mem/critbit0_test.c b/test/libc/mem/critbit0_test.c
index 23b79a569..f3222f645 100644
--- a/test/libc/mem/critbit0_test.c
+++ b/test/libc/mem/critbit0_test.c
@@ -17,11 +17,14 @@
 │ PERFORMANCE OF THIS SOFTWARE.                                                │
 ╚─────────────────────────────────────────────────────────────────────────────*/
 #include "libc/mem/critbit0.h"
+#include "libc/fmt/itoa.h"
 #include "libc/intrin/bits.h"
 #include "libc/mem/critbit0.h"
 #include "libc/mem/mem.h"
 #include "libc/runtime/runtime.h"
+#include "libc/stdio/rand.h"
 #include "libc/str/str.h"
+#include "libc/testlib/ezbench.h"
 #include "libc/testlib/testlib.h"
 
 struct Bog {
@@ -143,3 +146,26 @@ TEST(critbit0, manual_clear) {
   ASSERT_TRUE(critbit0_delete(&tree, "hi"));
   ASSERT_EQ(NULL, tree.root);
 }
+
+#define N 500
+
+char words[N][16];
+
+void GenerateWords(void) {
+  for (int i = 0; i < N; ++i) {
+    FormatInt32(words[i], rand());
+  }
+}
+
+void BuildTree(void) {
+  struct critbit0 tree = {0};
+  for (int i = 0; i < N; ++i) {
+    critbit0_insert(&tree, words[i]);
+  }
+  critbit0_clear(&tree);
+}
+
+BENCH(critbit0, bench) {
+  GenerateWords();
+  EZBENCH2("critbit0", donothing, BuildTree());
+}
diff --git a/test/libc/mem/malloc_test.c b/test/libc/mem/malloc_test.c
index fc535f155..50ffe6c5c 100644
--- a/test/libc/mem/malloc_test.c
+++ b/test/libc/mem/malloc_test.c
@@ -214,7 +214,7 @@ void *Worker(void *arg) {
 }
 
 BENCH(malloc, torture) {
-  int i, n = _getcpucount() * 2;
+  int i, n = __get_cpu_count() * 2;
   pthread_t *t = _gc(malloc(sizeof(pthread_t) * n));
   if (!n) return;
   printf("\nmalloc torture test w/ %d threads and %d iterations\n", n,
diff --git a/test/libc/stdio/popen_test.c b/test/libc/stdio/popen_test.c
index 541cf463f..c64c574e2 100644
--- a/test/libc/stdio/popen_test.c
+++ b/test/libc/stdio/popen_test.c
@@ -79,7 +79,7 @@ TEST(popen, semicolon) {
 
 TEST(popen, singleQuotes) {
   setenv("there", "a b c", true);
-  ASSERT_NE(NULL, (f = popen("echo -l 'hello $there' yo", "r")));
+  ASSERT_NE(NULL, (f = popen("echo 'hello $there'; echo yo", "r")));
   ASSERT_STREQ("hello $there\n", fgets(buf, sizeof(buf), f));
   ASSERT_STREQ("yo\n", fgets(buf, sizeof(buf), f));
   ASSERT_EQ(0, pclose(f));
@@ -88,7 +88,7 @@ TEST(popen, singleQuotes) {
 
 TEST(popen, doubleQuotes) {
   setenv("hello", "a b c", true);
-  ASSERT_NE(NULL, (f = popen("echo -l \"$hello there\"", "r")));
+  ASSERT_NE(NULL, (f = popen("echo \"$hello there\"", "r")));
   ASSERT_STREQ("a b c there\n", fgets(buf, sizeof(buf), f));
   ASSERT_EQ(0, pclose(f));
   CheckForFdLeaks();
@@ -96,7 +96,7 @@ TEST(popen, doubleQuotes) {
 
 TEST(popen, quoteless) {
   setenv("there", "a b c", true);
-  ASSERT_NE(NULL, (f = popen("echo -l hello a$there yo", "r")));
+  ASSERT_NE(NULL, (f = popen("echo hello; echo a$there; echo yo", "r")));
   ASSERT_STREQ("hello\n", fgets(buf, sizeof(buf), f));
   ASSERT_STREQ("aa b c\n", fgets(buf, sizeof(buf), f));  // mixed feelings
   ASSERT_STREQ("yo\n", fgets(buf, sizeof(buf), f));
diff --git a/test/libc/stdio/system_test.c b/test/libc/stdio/system_test.c
index e6bc87353..9c0b846b2 100644
--- a/test/libc/stdio/system_test.c
+++ b/test/libc/stdio/system_test.c
@@ -24,6 +24,7 @@
 #include "libc/paths.h"
 #include "libc/runtime/runtime.h"
 #include "libc/stdio/stdio.h"
+#include "libc/str/str.h"
 #include "libc/sysv/consts/o.h"
 #include "libc/sysv/consts/sig.h"
 #include "libc/testlib/ezbench.h"
@@ -45,6 +46,22 @@ void SetUp(void) {
   }
 }
 
+int pipefd[2];
+int stdoutBack;
+
+void CaptureStdout(void) {
+  ASSERT_NE(-1, (stdoutBack = dup(1)));
+  ASSERT_SYS(0, 0, pipe(pipefd));
+  ASSERT_NE(-1, dup2(pipefd[1], 1));
+}
+
+void RestoreStdout(void) {
+  ASSERT_SYS(0, 1, dup2(stdoutBack, 1));
+  ASSERT_SYS(0, 0, close(stdoutBack));
+  ASSERT_SYS(0, 0, close(pipefd[1]));
+  ASSERT_SYS(0, 0, close(pipefd[0]));
+}
+
 TEST(system, haveShell) {
   ASSERT_TRUE(system(0));
 }
@@ -71,20 +88,14 @@ TEST(system, testStdoutRedirect_withSpacesInFilename) {
 }
 
 TEST(system, testStderrRedirect_toStdout) {
-  if (IsAsan()) return;  // TODO(jart): fix me
-  int pipefd[2];
-  int stdoutBack = dup(1);
-  ASSERT_NE(-1, stdoutBack);
-  ASSERT_EQ(0, pipe(pipefd));
-  ASSERT_NE(-1, dup2(pipefd[1], 1));
+  CaptureStdout();
   int stderrBack = dup(2);
   ASSERT_NE(-1, stderrBack);
   char buf[5] = {0};
-
   ASSERT_NE(-1, dup2(1, 2));
   bool success = false;
   if (WEXITSTATUS(system("echo aaa 2>&1")) == 0) {
-    success = read(pipefd[0], buf, sizeof(buf) - 1) == (sizeof(buf) - 1);
+    success = read(pipefd[0], buf, 4) == (4);
   }
   ASSERT_NE(-1, dup2(stderrBack, 2));
   ASSERT_EQ(true, success);
@@ -97,15 +108,12 @@ TEST(system, testStderrRedirect_toStdout) {
   ASSERT_NE(-1, dup2(1, 2));
   success = false;
   if (WEXITSTATUS(system("./echo.com aaa 2>&1")) == 0) {
-    success = read(pipefd[0], buf, sizeof(buf) - 1) == (sizeof(buf) - 1);
+    success = read(pipefd[0], buf, 4) == (4);
   }
   ASSERT_NE(-1, dup2(stderrBack, 2));
   ASSERT_EQ(true, success);
   ASSERT_STREQ("aaa\n", buf);
-
-  ASSERT_NE(-1, dup2(stdoutBack, 1));
-  ASSERT_EQ(0, close(pipefd[1]));
-  ASSERT_EQ(0, close(pipefd[0]));
+  RestoreStdout();
 }
 
 TEST(system, and) {
@@ -168,49 +176,43 @@ TEST(system, exitStatusPreservedAfterSemiColon) {
   ASSERT_EQ(1, WEXITSTATUS(system("false; ")));
   ASSERT_EQ(1, WEXITSTATUS(system("./false.com;")));
   ASSERT_EQ(1, WEXITSTATUS(system("./false.com;")));
-  int pipefd[2];
-  int stdoutBack = dup(1);
-  ASSERT_NE(-1, stdoutBack);
-  ASSERT_EQ(0, pipe(pipefd));
-  ASSERT_NE(-1, dup2(pipefd[1], 1));
+  CaptureStdout();
   ASSERT_EQ(0, WEXITSTATUS(system("false; echo $?")));
-  char buf[3] = {0};
-  ASSERT_EQ(2, read(pipefd[0], buf, 2));
+  char buf[9] = {0};
+  ASSERT_EQ(2, read(pipefd[0], buf, 8));
   ASSERT_STREQ("1\n", buf);
   ASSERT_EQ(0, WEXITSTATUS(system("./false.com; echo $?")));
-  buf[0] = 0;
-  buf[1] = 0;
-  ASSERT_EQ(2, read(pipefd[0], buf, 2));
+  ASSERT_EQ(2, read(pipefd[0], buf, 8));
   ASSERT_STREQ("1\n", buf);
-  ASSERT_NE(-1, dup2(stdoutBack, 1));
-  ASSERT_EQ(0, close(pipefd[1]));
-  ASSERT_EQ(0, close(pipefd[0]));
+  ASSERT_EQ(0, WEXITSTATUS(system("echo -n hi")));
+  EXPECT_EQ(2, read(pipefd[0], buf, 8));
+  ASSERT_STREQ("hi", buf);
+  RestoreStdout();
+}
+
+TEST(system, globio) {
+  char buf[9] = {0};
+  CaptureStdout();
+  ASSERT_SYS(0, 0, touch("a", 0644));
+  ASSERT_SYS(0, 0, touch("b", 0644));
+  ASSERT_EQ(0, WEXITSTATUS(system("echo *")));
+  EXPECT_EQ(4, read(pipefd[0], buf, 8));
+  ASSERT_STREQ("a b\n", buf);
+  RestoreStdout();
 }
 
 TEST(system, allowsLoneCloseCurlyBrace) {
-  int pipefd[2];
-  int stdoutBack = dup(1);
-  ASSERT_NE(-1, stdoutBack);
-  ASSERT_EQ(0, pipe(pipefd));
-  ASSERT_NE(-1, dup2(pipefd[1], 1));
+  CaptureStdout();
   char buf[6] = {0};
-
   ASSERT_EQ(0, WEXITSTATUS(system("echo \"aaa\"}")));
-  ASSERT_EQ(sizeof(buf) - 1, read(pipefd[0], buf, sizeof(buf) - 1));
+  ASSERT_EQ(5, read(pipefd[0], buf, 5));
   ASSERT_STREQ("aaa}\n", buf);
-  buf[0] = 0;
-  buf[1] = 0;
-  buf[2] = 0;
-  buf[3] = 0;
-  buf[4] = 0;
+  bzero(buf, 6);
   testlib_extract("/zip/echo.com", "echo.com", 0755);
   ASSERT_EQ(0, WEXITSTATUS(system("./echo.com \"aaa\"}")));
-  ASSERT_EQ(sizeof(buf) - 1, read(pipefd[0], buf, sizeof(buf) - 1));
+  ASSERT_EQ(5, read(pipefd[0], buf, 5));
   ASSERT_STREQ("aaa}\n", buf);
-
-  ASSERT_NE(-1, dup2(stdoutBack, 1));
-  ASSERT_EQ(0, close(pipefd[1]));
-  ASSERT_EQ(0, close(pipefd[0]));
+  RestoreStdout();
 }
 
 TEST(system, glob) {
diff --git a/third_party/ggml/common.cc b/third_party/ggml/common.cc
index 09a9cd5c4..2f8e1d04c 100644
--- a/third_party/ggml/common.cc
+++ b/third_party/ggml/common.cc
@@ -88,7 +88,7 @@ static bool append_file_to_prompt(const char *path, gpt_params & params) {
 }
 
 bool gpt_params_parse(int argc, char ** argv, gpt_params & params) {
-    params.n_threads = std::min(20, std::max(1, _getcpucount() >> 1));
+    params.n_threads = std::min(20., (unsigned)__get_cpu_count() * .75);
 
     bool invalid_param = false;
     std::string arg;
diff --git a/third_party/ggml/common.h b/third_party/ggml/common.h
index 8a150d2ad..78851bbeb 100644
--- a/third_party/ggml/common.h
+++ b/third_party/ggml/common.h
@@ -21,7 +21,7 @@
 struct gpt_params {
     int32_t seed          = -1;   // RNG seed
     int32_t verbose       = 0;    // Logging verbosity
-    int32_t n_threads     = std::max(1, _getcpucount() >> 1);
+    int32_t n_threads     = std::max(20., (unsigned)__get_cpu_count() * .75);
     int32_t n_predict     = -1;   // new tokens to predict
     int32_t n_parts       = -1;   // amount of model parts (-1 = determine from model dimensions)
     int32_t n_ctx         = 512;  // context size
diff --git a/third_party/ggml/quantize.cc b/third_party/ggml/quantize.cc
index 838d0189f..9a0e70ddb 100644
--- a/third_party/ggml/quantize.cc
+++ b/third_party/ggml/quantize.cc
@@ -92,7 +92,7 @@ int main(int argc, char ** argv) {
         ftype = (enum llama_ftype)atoi(argv[3]);
     }
 
-    int nthread = argc > 4 ? atoi(argv[4]) : std::min(20, std::max(1, _getcpucount() >> 1));
+    int nthread = argc > 4 ? atoi(argv[4]) : std::min(20, std::max(1, __get_cpu_count() >> 1));
 
     const int64_t t_main_start_us = ggml_time_us();
 
diff --git a/third_party/lua/lunix.c b/third_party/lua/lunix.c
index 1ff267441..d2687fa3c 100644
--- a/third_party/lua/lunix.c
+++ b/third_party/lua/lunix.c
@@ -3532,7 +3532,7 @@ int LuaUnix(lua_State *L) {
   LuaSetIntField(L, "RUSAGE_CHILDREN", RUSAGE_CHILDREN);
   LuaSetIntField(L, "RUSAGE_BOTH", RUSAGE_BOTH);
 
-  LuaSetIntField(L, "ARG_MAX", __arg_max());
+  LuaSetIntField(L, "ARG_MAX", __get_arg_max());
   LuaSetIntField(L, "BUFSIZ", BUFSIZ);
   LuaSetIntField(L, "CLK_TCK", CLK_TCK);
   LuaSetIntField(L, "NAME_MAX", _NAME_MAX);
diff --git a/third_party/python/Modules/posixmodule.c b/third_party/python/Modules/posixmodule.c
index e6b4a237c..51240832d 100644
--- a/third_party/python/Modules/posixmodule.c
+++ b/third_party/python/Modules/posixmodule.c
@@ -10509,7 +10509,7 @@ os_cpu_count_impl(PyObject *module)
 /*[clinic end generated code: output=5fc29463c3936a9c input=e7c8f4ba6dbbadd3]*/
 {
     int ncpu;
-    ncpu = _getcpucount();
+    ncpu = __get_cpu_count();
     if (ncpu >= 1)
         return PyLong_FromLong(ncpu);
     else
diff --git a/third_party/radpajama/common-gptneox.cc b/third_party/radpajama/common-gptneox.cc
index 4a6b7ac02..6739678de 100644
--- a/third_party/radpajama/common-gptneox.cc
+++ b/third_party/radpajama/common-gptneox.cc
@@ -39,7 +39,7 @@
 // clang-format off
 
 bool gpt_params_parse(int argc, char ** argv, gpt_params & params) {
-    params.n_threads = std::min(20, std::max(1, (int)(_getcpucount() * 0.75)));
+    params.n_threads = std::min(20., (unsigned)__get_cpu_count() * 0.75);
 
     bool invalid_param = false;
     std::string arg;
diff --git a/third_party/radpajama/common-gptneox.h b/third_party/radpajama/common-gptneox.h
index 05e285617..f74a6283e 100644
--- a/third_party/radpajama/common-gptneox.h
+++ b/third_party/radpajama/common-gptneox.h
@@ -19,7 +19,7 @@
 
 struct gpt_params {
     int32_t seed          = -1;   // RNG seed
-    int32_t n_threads     = MIN(4, (int32_t) _getcpucount() * 0.75);
+    int32_t n_threads     = MIN(20., (unsigned) __get_cpu_count() * 0.75);
     int32_t n_predict     = 128;  // new tokens to predict
     int32_t n_parts       = -1;   // amount of model parts (-1 = determine from model dimensions)
     int32_t n_ctx         = 512;  // context size
diff --git a/tool/build/compile.c b/tool/build/compile.c
index 82997fffa..9e91e2213 100644
--- a/tool/build/compile.c
+++ b/tool/build/compile.c
@@ -314,7 +314,7 @@ void PrintMakeCommand(void) {
   appends(&output, "make MODE=");
   appends(&output, mode);
   appends(&output, " -j");
-  appendd(&output, buf, FormatUint64(buf, _getcpucount()) - buf);
+  appendd(&output, buf, FormatUint64(buf, __get_cpu_count()) - buf);
   appendw(&output, ' ');
   appends(&output, target);
 }
diff --git a/tool/build/mkdeps.c b/tool/build/mkdeps.c
index fd9e892ce..5f1c9067c 100644
--- a/tool/build/mkdeps.c
+++ b/tool/build/mkdeps.c
@@ -206,8 +206,8 @@ static void Crunch(void) {
   free(sources.p);
   sources.p = 0;
   sources.i = j;
-  if (!radix_sort_int64((const long *)sauces, sources.i) ||
-      !radix_sort_int64((const long *)edges.p, edges.i)) {
+  if (radix_sort_int64((const long *)sauces, sources.i) == -1 ||
+      radix_sort_int64((const long *)edges.p, edges.i) == -1) {
     DieOom();
   }
 }
diff --git a/tool/build/pledge.c b/tool/build/pledge.c
index 7e67632e9..efebdc7ea 100644
--- a/tool/build/pledge.c
+++ b/tool/build/pledge.c
@@ -163,9 +163,9 @@ static void GetOpts(int argc, char *argv[]) {
   g_fszquota = 256 * 1000 * 1000;
   if (!sysinfo(&si)) {
     g_memquota = si.totalram;
-    g_proquota = _getcpucount() + si.procs;
+    g_proquota = __get_cpu_count() + si.procs;
   } else {
-    g_proquota = _getcpucount() * 100;
+    g_proquota = __get_cpu_count() * 100;
     g_memquota = 4L * 1024 * 1024 * 1024;
   }
   while ((opt = getopt(argc, argv, "hnqkNVT:p:u:g:c:C:D:P:M:F:O:v:")) != -1) {
diff --git a/tool/net/lfuncs.c b/tool/net/lfuncs.c
index 60561081e..5a57014ac 100644
--- a/tool/net/lfuncs.c
+++ b/tool/net/lfuncs.c
@@ -131,7 +131,7 @@ int LuaGetCpuCore(lua_State *L) {
 }
 
 int LuaGetCpuCount(lua_State *L) {
-  lua_pushinteger(L, _getcpucount());
+  lua_pushinteger(L, __get_cpu_count());
   return 1;
 }