diff --git a/Makefile b/Makefile
index c83bc74..d970d9e 100644
--- a/Makefile
+++ b/Makefile
@@ -1,4 +1,8 @@
 SRCS = main.c output.c md4c.c
+
+SRCS += openat3.c openat4.c openat_append.c openatb_read.c openat_create.c \
+		openat_excl.c openat_readb.c openat_read.c openat_trunc.c openat_write.c
+
 OBJS = $(SRCS:.c=.o)
 DEPS = $(SRCS:.c=.d)
 
diff --git a/djbunix2.h b/djbunix2.h
new file mode 100644
index 0000000..9c38ab3
--- /dev/null
+++ b/djbunix2.h
@@ -0,0 +1,15 @@
+#ifndef DJBUNIX2_H
+#define DJBUNIX2_H
+
+int openat3(int fd, const char *file, unsigned int flags);
+int openat4(int fd, const char *file, unsigned int flags, unsigned int mode);
+int openat_read(int fd, const char *file);
+int openatb_read(int fd, const char *file);
+int openat_readb(int fd, const char *file);
+int openat_excl(int fd, const char *file);
+int openat_append(int fd, const char *file);
+int openat_create(int fd, const char *file);
+int openat_trunc(int fd, const char *file);
+int openat_write(int fd, const char *file);
+
+#endif /* DJBUNIX2_H */
diff --git a/main.c b/main.c
index c59bab1..6523780 100644
--- a/main.c
+++ b/main.c
@@ -10,9 +10,11 @@
 #include <errno.h>
 #include <skalibs/strerr2.h>
 #include <skalibs/buffer.h>
+#include <skalibs/djbunix.h>
 #include <err.h>
 #include "qmdoc.h"
 #include "output.h"
+#include "djbunix2.h"
 #include "md4c.h"
 
 const char *PROG = "qmdoc";
@@ -40,7 +42,7 @@ enum {
 };
 static struct css {
     const char *file;
-    char *buf;
+    off_t offset;
 } css[NB_CSS] = {
     { "struct.css" },
     { "common.css" },
@@ -56,6 +58,7 @@ struct page {
 struct ctx {
     int options;
     FILE *out;
+    stralloc sa_css;
     struct css *css;
     struct page *pages;
     int nb_pages;
@@ -191,7 +194,7 @@ enter_block(MD_BLOCKTYPE type, void *details, void *ctx_)
                 if (ctx->options & OPT_INLINE_CSS) {
                     for (int i = 0; i < NB_CSS; ++i) {
                         if (raw_str(f, "<style>") < 0
-                                || raw_str(f, ctx->css[i].buf) < 0
+                                || raw_str(f, ctx->sa_css.s + ctx->css[i].offset) < 0
                                 || raw_str(f, "</style>") < 0)
                             return ERR_IO;
                     }
@@ -633,67 +636,6 @@ convert_file(const char *file, struct ctx *ctx)
     return 0;
 }
 
-static int
-load_file(const char *file, char **dst)
-{
-    int fd = open(file, O_RDONLY | O_CLOEXEC | O_NONBLOCK);
-    if (fd < 0) ret(ERR_IO, "cannot open '%s'", file);
-
-    struct stat st;
-    if (fstat(fd, &st) < 0) {
-        warn("cannot stat '%s'", file);
-        close(fd);
-        return ERR_IO;
-    }
-
-    FILE *f = fdopen(fd, "re");
-    if (!f) {
-        warn("cannot open '%s'", file);
-        close(fd);
-        return ERR_IO;
-    }
-
-    *dst = malloc(st.st_size + 1);
-    if (!*dst) {
-        warn("cannot load '%s'", file);
-        fclose(f);
-        return ERR_MEM;
-    }
-
-    if (fread(*dst, 1, st.st_size, f) != st.st_size) {
-        free(*dst);
-        fclose(f);
-        retx(ERR_IO, "cannot read '%s'", file);
-    }
-    (*dst)[st.st_size] = 0;
-
-    fclose(f);
-    return 0;
-}
-
-static int
-write_file(int fdp, const char *path, const char *file, const char *data)
-{
-    int fd = openat(fdp, file, O_WRONLY | O_CREAT | O_EXCL | O_CLOEXEC | O_NONBLOCK, 0644);
-    if (fd < 0) ret(ERR_IO, "cannot create '%s/%s'", path, file);
-
-    FILE *f = fdopen(fd, "w");
-    if (!f) {
-        warn("cannot open '%s/%s'", path, file);
-        close(fd);
-        return ERR_IO;
-    }
-
-    size_t dlen = strlen(data);
-    if (fwrite(data, 1, dlen, f) != dlen) {
-        fclose(f);
-        retx(ERR_IO, "cannot write '%s/%s'", path, file);
-    }
-
-    fclose(f);
-    return 0;
-}
-
 static int
 load_page_from_file(const char *file, struct page *page)
 {
@@ -822,26 +764,36 @@ main (int argc, char *argv[])
         }
     }
 
+    struct ctx ctx = {
+        .options = options,
+        .sa_css = STRALLOC_ZERO,
+        .css = css,
+        .pages = pages,
+        .nb_pages = sizeof(pages) / sizeof(*pages),
+    };
+
     if (!(options & OPT_NO_CSS)) {
         outs((options & OPT_INLINE_CSS) ? "Loading" : "Copying");
         outse(" CSS files...");
         for (int i = 0; i < NB_CSS; ++i) {
-            r = load_file(css[i].file, &css[i].buf);
-            if (r < 0) return -r;
-            if (!(options & OPT_INLINE_CSS)) {
-                r = write_file(fddest, destdir, css[i].file, css[i].buf);
-                if (r < 0) return -r;
+            if ((options & OPT_INLINE_CSS)) {
+                css[i].offset = ctx.sa_css.len;
+                if (!openreadfileclose(css[i].file, &ctx.sa_css, 0))
+                    strerr_diefu3sys(ERR_IO, "load CSS from '", css[i].file, "'");
+            } else {
+                int from, to;
+                from = open_read(css[i].file);
+                if (from < 0) strerr_diefu3sys(ERR_IO, "open '", css[i].file, "'");
+                to = openat_excl(fddest, css[i].file);
+                if (to < 0) strerr_diefu5sys(ERR_IO, "create '", destdir, "/", css[i].file, "'");
+                if (fd_cat(from, to) < 0)
+                    strerr_diefu5sys(ERR_IO, "copy CSS to '", destdir, "/", css[i].file, "'");
+                fd_close(from);
+                fd_close(to);
             }
         }
     }
 
-    struct ctx ctx = {
-        .options = options,
-        .css = css,
-        .pages = pages,
-        .nb_pages = sizeof(pages) / sizeof(*pages),
-    };
-
     for (int i = optind; i < argc; ++i) {
         const char *sce = argv[i];
         size_t scelen = strlen(sce);
diff --git a/openat3.c b/openat3.c
new file mode 100644
index 0000000..d54b385
--- /dev/null
+++ b/openat3.c
@@ -0,0 +1,11 @@
+#include <fcntl.h>
+#include <errno.h>
+
+int
+openat3(int fd, const char *file, unsigned int flags)
+{
+    int r;
+    do r = openat(fd, file, flags);
+    while ((r < 0 && errno == EINTR));
+    return r;
+}
diff --git a/openat4.c b/openat4.c
new file mode 100644
index 0000000..61c5100
--- /dev/null
+++ b/openat4.c
@@ -0,0 +1,11 @@
+#include <fcntl.h>
+#include <errno.h>
+
+int
+openat4(int fd, const char *file, unsigned int flags, unsigned int mode)
+{
+    int r;
+    do r = openat(fd, file, flags, mode);
+    while ((r < 0 && errno == EINTR));
+    return r;
+}
diff --git a/openat_append.c b/openat_append.c
new file mode 100644
index 0000000..5ea9cab
--- /dev/null
+++ b/openat_append.c
@@ -0,0 +1,8 @@
+#include <fcntl.h>
+#include "djbunix2.h"
+
+int
+openat_append(int fd, const char *file)
+{
+    return openat4(fd, file, O_WRONLY | O_CREAT | O_APPEND | O_NONBLOCK, 0666);
+}
diff --git a/openat_create.c b/openat_create.c
new file mode 100644
index 0000000..09a75e1
--- /dev/null
+++ b/openat_create.c
@@ -0,0 +1,8 @@
+#include <fcntl.h>
+#include "djbunix2.h"
+
+int
+openat_create(int fd, const char *file)
+{
+    return openat4(fd, file, O_WRONLY | O_CREAT | O_NONBLOCK, 0666);
+}
diff --git a/openat_excl.c b/openat_excl.c
new file mode 100644
index 0000000..32ecfb5
--- /dev/null
+++ b/openat_excl.c
@@ -0,0 +1,8 @@
+#include <fcntl.h>
+#include "djbunix2.h"
+
+int
+openat_excl(int fd, const char *file)
+{
+    return openat4(fd, file, O_WRONLY | O_CREAT | O_EXCL | O_NONBLOCK, 0666);
+}
diff --git a/openat_read.c b/openat_read.c
new file mode 100644
index 0000000..528a38b
--- /dev/null
+++ b/openat_read.c
@@ -0,0 +1,8 @@
+#include <fcntl.h>
+#include "djbunix2.h"
+
+int
+openat_read(int fd, const char *file)
+{
+    return openat3(fd, file, O_RDONLY | O_NONBLOCK);
+}
diff --git a/openat_readb.c b/openat_readb.c
new file mode 100644
index 0000000..45539ea
--- /dev/null
+++ b/openat_readb.c
@@ -0,0 +1,15 @@
+#include <skalibs/djbunix.h>
+#include <fcntl.h>
+#include "djbunix2.h"
+
+int
+openat_readb(int fd, const char *file)
+{
+    int ffd = openat_read(fd, file);
+    if (ffd < 0) return -1;
+    if (ndelay_off(ffd) < 0) {
+        fd_close(ffd);
+        return -1;
+    }
+    return ffd;
+}
diff --git a/openat_trunc.c b/openat_trunc.c
new file mode 100644
index 0000000..8efc820
--- /dev/null
+++ b/openat_trunc.c
@@ -0,0 +1,8 @@
+#include <fcntl.h>
+#include "djbunix2.h"
+
+int
+openat_trunc(int fd, const char *file)
+{
+    return openat4(fd, file, O_WRONLY | O_CREAT | O_TRUNC | O_NONBLOCK, 0666);
+}
diff --git a/openat_write.c b/openat_write.c
new file mode 100644
index 0000000..df6ae80
--- /dev/null
+++ b/openat_write.c
@@ -0,0 +1,8 @@
+#include <fcntl.h>
+#include "djbunix2.h"
+
+int
+openat_write(int fd, const char *file)
+{
+    return openat3(fd, file, O_WRONLY | O_NONBLOCK);
+}
diff --git a/openatb_read.c b/openatb_read.c
new file mode 100644
index 0000000..ce8d5a5
--- /dev/null
+++ b/openatb_read.c
@@ -0,0 +1,8 @@
+#include <fcntl.h>
+#include "djbunix2.h"
+
+int
+openatb_read(int fd, const char *file)
+{
+    return openat3(fd, file, O_RDONLY);
+}