man3/: Add pagesunit

Signed-off-by: Alejandro Colomar <alx@kernel.org>

16 files changed, 1630 insertions, 6 deletions

diff --git a/man3/nxt_unit_ctx_alloc.3 b/man3/nxt_unit_ctx_alloc.3
new file mode 100644
index 000000000..d00db9e6d
--- /dev/null
+++ b/man3/nxt_unit_ctx_alloc.3
@@ -0,0 +1,132 @@
+.\" (C) 2023, NGINX, Inc.
+.\"
+.TH nxt_unit_ctx_alloc 3 (date) "NGINX Unit (unreleased)"
+.SH Name
+nxt_unit_ctx_alloc \- create context object for Unit app thread
+.SH Library
+NGINX Unit library
+.RI ( libunit ", " -lunit )
+.SH Synopsis
+.nf
+.B #include <nxt_unit.h>
+.PP
+.B [[gnu::malloc(nxt_unit_done)]]
+.BI "nxt_unit_ctx_t *_Nullable nxt_unit_ctx_alloc(nxt_unit_ctx_t *" ctx ,
+.BI "                                             void *_Nullable " data );
+.fi
+.SH Arguments
+.TP
+.I ctx
+Main context object for the application.
+It should have been created with
+.MR nxt_unit_init 3 .
+.TP
+.I data
+XXX
+.SH Description
+.MR nxt_unit_ctx_alloc 3
+creates a context object that will be used for a worker thread.
+.PP
+The next step after creating a thread context object
+is running the application thread;
+for that, see
+.MR nxt_unit_run 3 .
+.PP
+The context object created by this function should be
+destroyed by passing it to
+.MR nxt_unit_done 3 .
+.SH Return value
+A pointer to a context object on success,
+or NULL on error.
+.SH Errors
+Errors will be reported in the Unit debug log.
+.IP \[bu] 3
+.MR pthread_mutex_init 3
+failed.
+.PD 0
+.IP \[bu]
+.MR socketpair 2
+failed.
+.IP \[bu]
+.MR setsockopt 2
+failed.
+.IP \[bu]
+.MR memfd_create 2
+failed.
+.IP \[bu]
+.MR shm_open 2
+failed.
+.IP \[bu]
+.MR ftruncate 2
+failed.
+.IP \[bu]
+.MR mmap 2
+failed.
+.IP \[bu]
+.MR sendmsg 2
+failed.
+.IP \[bu]
+.MR nxt_unit_malloc 3
+failed.
+.IP \[bu]
+.I nxt_unit_init_t::callbacks.port_send
+failed.
+.IP \[bu]
+Internal hash table failure.
+.PD
+.SH Examples
+See
+.MR nxt_unit_init 3
+for an example where this
+.IR worker ()
+function is used.
+.PP
+.EX
+#include <pthread.h>
+#include <stddef.h>
+#include <stdint.h>
+\&
+#include <nxt_unit.h>
+\&
+void *
+worker(void *main_ctx)
+{
+    int             rc;
+    nxt_unit_ctx_t  *ctx;
+\&
+    ctx = nxt_unit_ctx_alloc(main_ctx, NULL);
+    if (ctx == NULL) {
+        pthread_exit(NULL);
+    }
+\&
+    nxt_unit_debug(ctx, "start worker");
+    rc = nxt_unit_run(ctx);
+    nxt_unit_debug(ctx, "worker finished with %d code", rc);
+\&
+    nxt_unit_done(ctx);
+\&
+    pthread_exit((void *) (intptr_t) rc);
+}
+.EE
+.SH Copyright
+(C) 2017-2023, NGINX, Inc.
+.PP
+SPDX-License-Identifier: Apache-2.0
+.SH See also
+.MR nxt_unit_done 3 ,
+.MR nxt_unit_run 3 ,
+.MR pthread_create 3 ,
+.MR pthread_exit 3 ,
+.MR unitd 8
+.PP
+Website
+.UR https://unit.nginx.org
+.UE
+.PP
+Mailing list
+.UR https://mailman.nginx.org/mailman/listinfo/unit
+.UE
+.PP
+GitHub
+.UR https://github.com/nginx/unit
+.UE
diff --git a/man3/nxt_unit_done.3 b/man3/nxt_unit_done.3
new file mode 100644
index 000000000..31fd1b620
--- /dev/null
+++ b/man3/nxt_unit_done.3
@@ -0,0 +1,54 @@
+.\" (C) 2023, NGINX, Inc.
+.\"
+.TH nxt_unit_done 3 (date) "NGINX Unit (unreleased)"
+.SH Name
+nxt_unit_done \- destroy context object in Unit app
+.SH Library
+NGINX Unit library
+.RI ( libunit ", " -lunit )
+.SH Synopsis
+.nf
+.B #include <nxt_unit.h>
+.PP
+.BI "void nxt_unit_done(nxt_unit_ctx_t *" ctx );
+.fi
+.SH Arguments
+.TP
+.I ctx
+Context object to be destroyed.
+It should have been created with
+.MR nxt_unit_init 3
+or
+.MR nxt_unit_ctx_alloc 3 .
+.SH Description
+.MR nxt_unit_done 3
+destroys a context object in a Unit application.
+.SH Return value
+None.
+.SH Errors
+None.
+.SH Examples
+See
+.MR nxt_unit_init 3
+and
+.MR nxt_unit_ctx_alloc 3 .
+.SH Copyright
+(C) 2017-2023, NGINX, Inc.
+.PP
+SPDX-License-Identifier: Apache-2.0
+.SH See also
+.MR nxt_unit_ctx_alloc 3 ,
+.MR nxt_unit_init 3 ,
+.MR unitd 8
+.PP
+Website
+.UR https://unit.nginx.org
+.UE
+.PP
+Mailing list
+.UR https://mailman.nginx.org/mailman/listinfo/unit
+.UE
+.PP
+GitHub
+.UR https://github.com/nginx/unit
+.UE
diff --git a/man3/nxt_unit_init.3 b/man3/nxt_unit_init.3
new file mode 100644
index 000000000..8b192cb31
--- /dev/null
+++ b/man3/nxt_unit_init.3
@@ -0,0 +1,166 @@
+.\" (C) 2023, NGINX, Inc.
+.\"
+.TH nxt_unit_init 3 (date) "NGINX Unit (unreleased)"
+.SH Name
+nxt_unit_init \- initialize Unit app
+.SH Library
+NGINX Unit library
+.RI ( libunit ", " -lunit )
+.SH Synopsis
+.nf
+.B #include <nxt_unit.h>
+.PP
+.B [[gnu::malloc(nxt_unit_done)]]
+.BI "nxt_unit_ctx_t *_Nullable nxt_unit_init(nxt_unit_init_t *" init );
+.fi
+.SH Arguments
+.TP
+.I init
+Object that specifies how the application should work.
+.SH Description
+.MR nxt_unit_init 3
+initializes a Unit application.
+.PP
+It creates a main context object that
+is necessary for most other libunit functions.
+.PP
+The next step after initializing the application is running it;
+for that, see
+.MR nxt_unit_run 3 .
+.PP
+The context object created by this function should be
+destroyed by passing it to
+.MR nxt_unit_done 3 .
+.SH Return value
+A pointer to a context object on success,
+or NULL on error.
+.SH Errors
+Errors will be reported in the Unit debug log.
+.IP \[bu] 3
+.MR pthread_mutex_init 3
+failed.
+.PD 0
+.IP \[bu]
+.MR nxt_unit_malloc 3
+failed.
+.IP \[bu]
+.I init->callbacks.request_handler
+is NULL.
+.PD
+.SH Examples
+.EX
+#include <pthread.h>
+#include <stddef.h>
+#include <stdlib.h>
+#include <string.h>
+#include <strings.h>
+#include <sys/types.h>
+\&
+#include <nxt_unit.h>
+\&
+// See \c
+.MR nxt_unit_response_add_field 3 .
+void request_handler(nxt_unit_request_info_t *req);
+\&
+// See \c
+.MR nxt_unit_ctx_alloc 3 .
+void *worker(void *main_ctx);
+\&
+static int ready_handler(nxt_unit_ctx_t *main_ctx);
+\&
+static ssize_t  nthreads;
+static pthread_t  *threads;
+\&
+int
+main(int argc, char **argv)
+{
+    int              err;
+    void             *ret;
+    nxt_unit_ctx_t   *ctx;
+    nxt_unit_init_t  init;
+\&
+    if (argc == 3 && strcmp(argv[1], "\-t") == 0) {
+        nthreads = atoi(argv[2]);
+    }
+\&
+    bzero(&init, sizeof(nxt_unit_init_t));
+    init.callbacks.request_handler = &request_handler;
+    init.callbacks.ready_handler = &ready_handler;
+\&
+    ctx = nxt_unit_init(&init);
+    if (ctx == NULL) {
+        exit(EXIT_FAILURE);
+    }
+\&
+    err = nxt_unit_run(ctx);
+    nxt_unit_debug(ctx, "main worker finished with %d code", err);
+\&
+    for (ssize_t i = 0; i < nthreads; i++) {
+        err = pthread_join(threads[i], &ret);
+\&
+        if (err != 0) {
+            nxt_unit_alert(ctx, "pthread_join(#%zd) failed: %s (%d)",
+                                i, strerror(err), err);
+        } else {
+            nxt_unit_debug(ctx, "pthread_join(#%zd) retval: %"PRIdPTR,
+                                i, (intptr_t) ret);
+        }
+    }
+\&
+    nxt_unit_free(ctx, threads);
+\&
+    nxt_unit_done(ctx);
+    nxt_unit_debug(NULL, "main worker done");
+\&
+    exit(EXIT_SUCCESS);
+}
+\&
+static int
+ready_handler(nxt_unit_ctx_t *ctx)
+{
+    int  err;
+\&
+    nxt_unit_debug(ctx, "ready");
+\&
+    if (nthreads <= 1) {
+        return NXT_UNIT_OK;
+    }
+\&
+    threads = nxt_unit_malloc(ctx, sizeof(pthread_t) * (nthreads \- 1));
+    if (threads == NULL) {
+        return NXT_UNIT_ERROR;
+    }
+\&
+    // See \c
+.MR nxt_unit_ctx_alloc 3 .
+    for (ssize_t i = 0; i < nthreads \- 1; i++) {
+        err = pthread_create(&threads[i], NULL, &worker, ctx);
+        if (err != 0) {
+            return NXT_UNIT_ERROR;
+        }
+    }
+\&
+    return NXT_UNIT_OK;
+}
+.EE
+.SH Copyright
+(C) 2017-2023, NGINX, Inc.
+.PP
+SPDX-License-Identifier: Apache-2.0
+.SH See also
+.MR nxt_unit_ctx_alloc 3 ,
+.MR nxt_unit_run 3 ,
+.MR nxt_unit_done 3 ,
+.MR unitd 8
+.PP
+Website
+.UR https://unit.nginx.org
+.UE
+.PP
+Mailing list
+.UR https://mailman.nginx.org/mailman/listinfo/unit
+.UE
+.PP
+GitHub
+.UR https://github.com/nginx/unit
+.UE
diff --git a/man3/nxt_unit_log.3 b/man3/nxt_unit_log.3
new file mode 100644
index 000000000..8c310d358
--- /dev/null
+++ b/man3/nxt_unit_log.3
@@ -0,0 +1,91 @@
+.\" (C) 2023, NGINX, Inc.
+.\"
+.TH nxt_unit_log 3 (date) "NGINX Unit (unreleased)"
+.SH Name
+nxt_unit_log, nxt_unit_alert, nxt_unit_error, nxt_unit_warn, nxt_unit_debug
+\- print messages to the debug log
+.SH Library
+NGINX Unit library
+.RI ( libunit ", " -lunit )
+.SH Synopsis
+.nf
+.B #include <nxt_unit.h>
+.PP
+.B enum {
+.B "    NXT_UNIT_LOG_ALERT,"
+.B "    NXT_UNIT_LOG_ERR,"
+.B "    NXT_UNIT_LOG_WARN,"
+.B "    NXT_UNIT_LOG_NOTICE,"
+.B "    NXT_UNIT_LOG_INFO,"
+.B "    NXT_UNIT_LOG_DEBUG,"
+.B };
+.PP
+.B [[gnu::format(printf, 3, 4)]]
+.BI "void nxt_unit_log(nxt_unit_ctx_t *_Nullable " ctx ", int " level ,
+.BI "                  const char *" fmt ", ...);"
+.PP
+.BI "#define nxt_unit_alert(" ctx ", " fmt ", ...)  \fR/* ... */\fP"
+.BI "#define nxt_unit_error(" ctx ", " fmt ", ...)  \fR/* ... */\fP"
+.BI "#define nxt_unit_warn(" ctx ", " fmt ", ...)   \fR/* ... */\fP"
+.BI "#define nxt_unit_debug(" ctx ", " fmt ", ...)  \fR/* ... */\fP"
+.fi
+.SH Arguments
+.TP
+.I ctx
+Thread or main context object.
+See
+.MR nxt_unit_init 3
+and
+.MR nxt_unit_ctx_alloc 3 .
+If NULL is passed,
+the output will be printed to standard error.
+.TP
+.I level
+Log level (see the
+.IR enum ).
+.TP
+.I fmt
+See
+.MR snprintf 3 .
+.SH Description
+.MR nxt_unit_log 3
+writes a formatted string into the Unit debug log,
+prefixed with information about the application,
+and appended by a new-line character.
+.PP
+The macros are just wrappers around
+.MR nxt_unit_log 3
+that pass a specific log level.
+.SH Return value
+None.
+.SH Errors
+If these functions fail to write to the Unit debug log,
+they will fall back to standard error.
+.SH Files
+.TP
+.I /usr/local/var/log/unit/unit.log
+Unit debug log.
+See
+.MR unitd 8 .
+.SH Examples
+See
+.MR nxt_unit_init 3 .
+.SH Copyright
+(C) 2017-2023, NGINX, Inc.
+.PP
+SPDX-License-Identifier: Apache-2.0
+.SH See also
+.MR nxt_unit_req_log 3 ,
+.MR unitd 8 .
+.PP
+.UR https://unit.nginx.org
+Website
+.UE
+.PP
+.UR https://mailman.nginx.org/mailman/listinfo/unit
+Mailing list
+.UE
+.PP
+.UR https://github.com/nginx/unit
+GitHub
+.UE
diff --git a/man3/nxt_unit_malloc.3 b/man3/nxt_unit_malloc.3
new file mode 100644
index 000000000..752fd4183
--- /dev/null
+++ b/man3/nxt_unit_malloc.3
@@ -0,0 +1,70 @@
+.\" (C) 2023, NGINX, Inc.
+.\"
+.TH nxt_unit_malloc 3 (date) "NGINX Unit (unreleased)"
+.SH Name
+nxt_unit_malloc \-
+.MR malloc 3
+wrapper with logging
+.SH Library
+NGINX Unit library
+.RI ( libunit ", " -lunit )
+.SH Synopsis
+.nf
+.B #include <nxt_unit.h>
+.PP
+.B [[gnu::malloc(nxt_unit_free)]]
+.BI "void *_Nullable nxt_unit_malloc(nxt_unit_ctx_t *_Nullable " ctx ,
+.BI "                                size_t " size );
+.BI "void nxt_unit_free(nxt_unit_ctx_t *_Nullable " ctx ", void *_Nullable " ptr );
+.fi
+.SH Arguments
+.TP
+.I ctx
+See
+.MR nxt_unit_log 3 .
+.TP
+.I size
+See
+.MR malloc 3 .
+.TP
+.I ptr
+See
+.MR free 3 .
+.SH Description
+.MR nxt_unit_malloc 3
+and
+.MR nxt_unit_free 3
+are equivalent to
+.MR malloc 3
+and
+.MR free 3 ,
+but log in the Unit debug log.
+.SH Return value
+See
+.MR malloc 3 .
+.SH Errors
+Errors will be reported in the Unit debug log.
+.IP \[bu] 3
+.MR malloc 3
+failed.
+.SH Examples
+See
+.MR nxt_unit_init 3 .
+.SH Copyright
+(C) 2017-2023, NGINX, Inc.
+.PP
+SPDX-License-Identifier: Apache-2.0
+.SH See also
+.MR malloc 3 .
+.PP
+Website
+.UR https://unit.nginx.org
+.UE
+.PP
+Mailing list
+.UR https://mailman.nginx.org/mailman/listinfo/unit
+.UE
+.PP
+GitHub
+.UR https://github.com/nginx/unit
+.UE
diff --git a/man3/nxt_unit_req_log.3 b/man3/nxt_unit_req_log.3
new file mode 100644
index 000000000..b1a665b49
--- /dev/null
+++ b/man3/nxt_unit_req_log.3
@@ -0,0 +1,76 @@
+.\" (C) 2023, NGINX, Inc.
+.\"
+.TH nxt_unit_log 3 (date) "NGINX Unit (unreleased)"
+.SH Name
+nxt_unit_req_log,
+nxt_unit_req_alert,
+nxt_unit_req_error,
+nxt_unit_req_warn,
+nxt_unit_req_debug
+\-
+print messages to the debug log related to a request in a Unit app
+.SH Library
+NGINX Unit library
+.RI ( libunit ", " -lunit )
+.SH Synopsis
+.nf
+.B #include <nxt_unit.h>
+.PP
+.B [[gnu::format(printf, 3, 4)]]
+.BI "void nxt_unit_req_log(nxt_unit_request_info_t *_Nullable " req ,
+.BI "                      int " level ", const char *" fmt ", ...);"
+.PP
+.BI "#define nxt_unit_req_alert(" req ", " fmt ", ...)  \fR/* ... */\fP"
+.BI "#define nxt_unit_req_error(" req ", " fmt ", ...)  \fR/* ... */\fP"
+.BI "#define nxt_unit_req_warn(" req ", " fmt ", ...)   \fR/* ... */\fP"
+.BI "#define nxt_unit_req_debug(" req ", " fmt ", ...)  \fR/* ... */\fP"
+.fi
+.SH Arguments
+.TP
+.I req
+Request object.
+.TP
+.I level
+Log level
+.TP
+.I fmt
+See
+.MR snprintf 3 .
+.SH Description
+.MR nxt_unit_req_log 3
+is similar to
+.MR nxt_unit_log 3 ,
+but it associates the log to a specific request.
+.SH Return value
+None.
+.SH Errors
+If these functions fail to write to the Unit debug log,
+they will fall back to standard error.
+.SH Files
+.TP
+.I /usr/local/var/log/unit/unit.log
+Unit debug log.
+See
+.MR unitd 8 .
+.SH Examples
+See
+.MR nxt_unit_response_add_field 3 .
+.SH Copyright
+(C) 2017-2023, NGINX, Inc.
+.PP
+SPDX-License-Identifier: Apache-2.0
+.SH See also
+.MR nxt_unit_log 3 ,
+.MR unitd 8 .
+.PP
+.UR https://unit.nginx.org
+Website
+.UE
+.PP
+.UR https://mailman.nginx.org/mailman/listinfo/unit
+Mailing list
+.UE
+.PP
+.UR https://github.com/nginx/unit
+GitHub
+.UE
diff --git a/man3/nxt_unit_request_read.3 b/man3/nxt_unit_request_read.3
new file mode 100644
index 000000000..ba07b4744
--- /dev/null
+++ b/man3/nxt_unit_request_read.3
@@ -0,0 +1,142 @@
+.\" (C) 2023, NGINX, Inc.
+.\"
+.TH nxt_unit_request_read 3 (date) "NGINX Unit (unreleased)"
+.SH Name
+nxt_unit_request_read
+\-
+read  content of a response in Unit app
+.SH Library
+NGINX Unit library
+.RI ( libunit ", " -lunit )
+.SH Synopsis
+.nf
+.B #include <nxt_unit.h>
+.PP
+.BI "ssize_t nxt_unit_request_read(nxt_unit_request_info_t *" req ,
+.BI "                              void " dst [. size "], size_t " size );
+.fi
+.SH Arguments
+.TP
+.I req
+Request object.
+.TP
+.I dst
+Buffer where the request message body will be written.
+It's a buffer of
+.I size
+bytes.
+.SH Description
+.MR nxt_unit_request_read 3
+copies the client request message body into a buffer.
+.PP
+This function does not read
+the header fields nor the request line,
+which are available in
+.IR req\->request .
+.SH Return value
+The number of bytes read on success,
+or \-1 on error.
+.SH Errors
+Errors will be reported in the Unit debug log.
+.TP
+.B NXT_UNIT_ERROR
+.RS
+.PD 0
+.IP \[bu] 3
+Failed to read content.
+.PD
+.RE
+.SH Examples
+Below is a request and response pair,
+and the source code to produce it.
+It implements an echo web application.
+.PP
+See
+.MR nxt_unit_init 3
+for an example where the
+.IR request_handler ()
+function defined below is used.
+.SS Request
+.EX
+.RB "$ " "echo \-e \[aq]foo\enbar\[aq] | curl \-\-data\-binary @\- localhost;"
+foo
+bar
+.EE
+.SS C code
+.EX
+#define _GNU_SOURCE
+#include <string.h>
+\&
+#include <nxt_unit.h>
+\&
+void
+request_handler(nxt_unit_request_info_t *req)
+{
+    int             rc;
+    ssize_t         res;
+    nxt_unit_buf_t  *buf;
+\&
+    rc = nxt_unit_response_init(req, 200, 1, strlen("Content\-Type")
+                                             + strlen("text/plain"));
+    if (rc != 0) {
+        goto fail;
+    }
+\&
+    rc = nxt_unit_response_add_field(req, "Content\-Type",
+                                          strlen("Content\-Type"),
+                                          "text/plain",
+                                          strlen("text/plain"));
+    if (rc != 0) {
+        goto fail;
+    }
+\&
+    rc = nxt_unit_response_send(req);
+    if (rc != 0) {
+        goto fail;
+    }
+\&
+    while (req\->content_length) {
+        buf = nxt_unit_response_buf_alloc(req, req\->content_length);
+        if (buf == NULL) {
+            rc = NXT_UNIT_ERROR;
+            goto fail;
+        }
+\&
+        res = nxt_unit_request_read(req, buf\->free,
+                                    buf\->end \- buf\->free);
+        if (res == \-1) {
+            goto fail;
+        }
+\&
+        buf\->free += res;
+\&
+        rc = nxt_unit_buf_send(buf);
+        if (rc != 0) {
+            goto fail;
+        }
+    }
+\&
+fail:
+    nxt_unit_request_done(req, rc);
+}
+.EE
+.SH Copyright
+(C) 2017-2023, NGINX, Inc.
+.PP
+SPDX-License-Identifier: Apache-2.0
+.SH See also
+.MR nxt_unit_init 3 ,
+.MR nxt_unit_response_init 3 ,
+.MR unitd 8
+.PP
+.UR https://unit.nginx.org
+Website
+.UE
+.PP
+.UR https://mailman.nginx.org/mailman/listinfo/unit
+Mailing list
+.UE
+.PP
+.UR https://github.com/nginx/unit
+GitHub
+.UE
diff --git a/man3/nxt_unit_response_add_content.3 b/man3/nxt_unit_response_add_content.3
new file mode 100644
index 000000000..037cec783
--- /dev/null
+++ b/man3/nxt_unit_response_add_content.3
@@ -0,0 +1,91 @@
+.\" (C) 2023, NGINX, Inc.
+.\"
+.TH nxt_unit_response_add_content 3 (date) "NGINX Unit (unreleased)"
+.SH Name
+nxt_unit_response_add_content \- add content to HTTP response in Unit app
+.SH Library
+NGINX Unit library
+.RI ( libunit ", " -lunit )
+.SH Synopsis
+.nf
+.B #include <nxt_unit.h>
+.PP
+.BI "int nxt_unit_response_add_content(nxt_unit_request_info_t *" req ,
+.BI "                                  const void " content [. size ],
+.BI "                                  uint32_t " size );
+.fi
+.SH Arguments
+.TP
+.I req
+Request object.
+.TP
+.I content
+Content of the response.
+It's a buffer of
+.I size
+bytes.
+.SH Description
+.MR nxt_unit_response_add_content 3
+adds content to an HTTP response.
+.PP
+The response should have been initialized previously with
+.MR nxt_unit_response_init 3 .
+.PP
+The response should have enough remaining buffer size available.
+If there's not enough,
+more buffer can be allocated with
+.MR nxt_unit_response_buff_alloc 3 .
+.PP
+This function can be called several times,
+and all contents will be merged into the (chunked) response.
+After content is added to the response,
+it should be sent with
+.MR nxt_unit_response_send 3 .
+.SH Return value
+0 on success,
+or a non-zero error code on error.
+.SH Errors
+Errors will be reported in the Unit debug log.
+.TP
+.B NXT_UNIT_ERROR
+.RS
+.PD 0
+.IP \[bu] 3
+Response not initialized.
+.IP \[bu]
+Response already sent.
+.IP \[bu]
+Content is longer than the response buffer.
+.PD
+.RE
+.SH Examples
+See
+.MR nxt_unit_response_add_field 3 .
+.SH Copyright
+(C) 2017-2023, NGINX, Inc.
+.PP
+SPDX-License-Identifier: Apache-2.0
+.SH See also
+.MR nxt_unit_init 3 ,
+.MR nxt_unit_response_init 3 ,
+.MR nxt_unit_response_add_field 3 ,
+.MR nxt_unit_response_buf_alloc 3 ,
+.MR nxt_unit_response_send 3 ,
+.MR nxt_unit_request_done 3 ,
+.MR unitd 8
+.PP
+.UR https://www.rfc-editor.org/\:rfc/\:rfc9112\:#section-5
+RFC 9112, section 5: Field Syntax
+.UE
+.PP
+Website
+.UR https://unit.nginx.org
+.UE
+.PP
+Mailing list
+.UR https://mailman.nginx.org/\:mailman/\:listinfo/\:unit
+.UE
+.PP
+GitHub
+.UR https://github.com/\:nginx/\:unit
+.UE
diff --git a/man3/nxt_unit_response_add_field.3 b/man3/nxt_unit_response_add_field.3
new file mode 100644
index 000000000..b47e37c3f
--- /dev/null
+++ b/man3/nxt_unit_response_add_field.3
@@ -0,0 +1,162 @@
+.\" (C) 2023, NGINX, Inc.
+.\"
+.TH nxt_unit_response_add_field 3 (date) "NGINX Unit (unreleased)"
+.SH Name
+nxt_unit_response_add_field \- add field to HTTP response in Unit app
+.SH Library
+NGINX Unit library
+.RI ( libunit ", " -lunit )
+.SH Synopsis
+.nf
+.B #include <nxt_unit.h>
+.PP
+.BI "int nxt_unit_response_add_field(nxt_unit_request_info_t *" req ,
+.BI "                                const char " name [. nlen "], uint8_t " nlen ,
+.BI "                                const char " value [. vlen "], uint32_t " vlen );
+.fi
+.SH Arguments
+.TP
+.I req
+Request object.
+.TP
+.I name
+Name of the field.
+It is a character sequence of length
+.IR nlen .
+.TP
+.I value
+Value of the field.
+It is a character sequence of length
+.IR vlen .
+.SH Description
+.MR nxt_unit_response_add_field 3
+adds a field to the header of an HTTP response.
+.PP
+The response should have been initialized previously with
+.MR nxt_unit_response_init 3 .
+.PP
+If the
+.B \%Content\-Length
+header field is not sent,
+Unit will send a
+.B \%Transfer-Encoding:\ chunked
+response,
+and will produce the header if necessary.
+.SH Return value
+0 on success,
+or a non-zero error code on error.
+.SH Errors
+Errors will be reported in the Unit debug log.
+.TP
+.B NXT_UNIT_ERROR
+.RS
+.PD 0
+.IP \[bu] 3
+Response not initialized.
+.IP \[bu]
+Too many response fields.
+.IP \[bu]
+Field is longer than the response buffer.
+.PD
+.RE
+.SH Examples
+Below is a request and response pair,
+and the source code to produce it.
+.PP
+See
+.MR nxt_unit_init 3
+for an example where the
+.IR request_handler ()
+function defined below is used.
+.SS Request
+.EX
+.RB $ " echo \-e \[aq]GET / HTTP/1.1\er\enHost: _\en\[aq] | ncat localhost 80;"
+HTTP/1.1 200 OK
+Content\-Type: text/plain
+Content\-Length: 42
+Server: Unit/1.30.0
+Date: Sat, 22 May 2023 20:45:50 GMT
+\&
+Hello world!
+.EE
+.SS C code
+.EX
+#include <string.h>
+\&
+#include <nxt_unit.h>
+\&
+void
+request_handler(nxt_unit_request_info_t *req)
+{
+    int  rc;
+\&
+    rc = nxt_unit_response_init(req, 200, 2, strlen("Content\-Type")
+                                             + strlen("text/plain")
+                                             + strlen("Content\-Length")
+                                             + strlen("42")
+                                             + strlen("Hello world!\en"));
+    if (rc != 0) {
+        goto fail;
+    }
+\&
+    rc = nxt_unit_response_add_field(req, "Content\-Type",
+                                          strlen("Content\-Type"),
+                                          "text/plain",
+                                          strlen("text/plain"));
+    if (rc != 0) {
+        goto fail;
+    }
+\&
+    rc = nxt_unit_response_add_field(req, "Content\-Length",
+                                          strlen("Content\-Length"),
+                                          "42",
+                                          strlen("42"));
+    if (rc != 0) {
+        goto fail;
+    }
+\&
+    rc = nxt_unit_response_add_content(req, "Hello", strlen("Hello"));
+    if (rc != 0) {
+        goto fail;
+    }
+    rc = nxt_unit_response_add_content(req, " world!\en",
+                                            strlen(" world!\en"));
+    if (rc != 0) {
+        goto fail;
+    }
+\&
+    rc = nxt_unit_response_send(req);
+\&
+    nxt_unit_req_debug(req, "Response sent.");
+\&
+fail:
+    nxt_unit_request_done(req, rc);
+}
+.EE
+.SH Copyright
+(C) 2017-2023, NGINX, Inc.
+.PP
+SPDX-License-Identifier: Apache-2.0
+.SH See also
+.MR nxt_unit_init 3 ,
+.MR nxt_unit_response_init 3 ,
+.MR nxt_unit_response_add_content 3 ,
+.MR nxt_unit_response_send 3 ,
+.MR nxt_unit_request_done 3 ,
+.MR unitd 8
+.PP
+.UR https://www.rfc-editor.org/\:rfc/\:rfc9112\:#section-5
+RFC 9112, section 5: Field Syntax
+.UE
+.PP
+Website
+.UR https://unit.nginx.org
+.UE
+.PP
+Mailing list
+.UR https://mailman.nginx.org/\:mailman/\:listinfo/\:unit
+.UE
+.PP
+GitHub
+.UR https://github.com/\:nginx/\:unit
+.UE
diff --git a/man3/nxt_unit_response_buf_alloc.3 b/man3/nxt_unit_response_buf_alloc.3
new file mode 100644
index 000000000..2a429b270
--- /dev/null
+++ b/man3/nxt_unit_response_buf_alloc.3
@@ -0,0 +1,194 @@
+.\" (C) 2023, NGINX, Inc.
+.\"
+.TH nxt_unit_response_buf_alloc 3 (date) "NGINX Unit (unreleased)"
+.SH Name
+nxt_unit_response_buf_alloc,
+nxt_unit_buf_send
+\-
+allocate buffer for response in Unit app
+.SH Library
+NGINX Unit library
+.RI ( libunit ", " -lunit )
+.SH Synopsis
+.nf
+.B #include <nxt_unit.h>
+.PP
+.B [[gnu::malloc(nxt_unit_buf_send)]]
+.B nxt_unit_buf_t *_Nullable
+.BI "nxt_unit_response_buf_alloc(nxt_unit_request_info_t *" req ", uint32_t " size );
+.PP
+.BI "int nxt_unit_buf_send(nxt_unit_buf_t *" buf );
+.fi
+.SH Arguments
+.TP
+.I req
+Request object.
+.TP
+.I size
+Size of the buffer.
+.TP
+.I buf
+Buffer.
+.SH Description
+.MR nxt_unit_response_buf_alloc 3
+allocates a buffer for a response to a request,
+or for a chunk of it.
+.PP
+.MR nxt_unit_buf_send 3
+sends and deallocates the buffer previously allocated with
+.MR nxt_unit_response_buf_alloc 3 .
+.SH Return value
+.TP
+.MR nxt_unit_response_buf_alloc 3
+A pointer to the allocated buffer on success,
+or NULL on error.
+.TP
+.MR nxt_unit_buf_send 3
+0 on success,
+or a non-zero error code on error.
+.SH Errors
+Errors will be reported in the Unit debug log.
+.TP
+.B NXT_UNIT_ERROR
+.RS
+.PD 0
+.IP \[bu] 3
+.I size
+was too big.
+.IP \[bu]
+Allocation failed.
+.IP \[bu]
+Failed to share the buffer with
+.MR unitd 8 .
+.PD
+.RE
+.SH Examples
+Below is a request and response pair,
+and the source code to produce it.
+.PP
+See
+.MR nxt_unit_init 3
+for an example where the
+.IR request_handler ()
+function defined below is used.
+.SS Request
+.EX
+.RB $ " echo \-e \[aq]GET / HTTP/1.1\er\enHost: _\en\[aq] | ncat localhost 80;"
+HTTP/1.1 200 OK
+Content\-Type: text/plain
+Server: Unit/1.30.0
+Date: Sat, 20 May 2023 19:08:22 GMT
+Transfer\-Encoding: chunked
+\&
+22
+Hello world!
+But send this first.
+\&
+15
+Some extra contents.
+\&
+e
+And some more
+\&
+0
+\&
+.EE
+.SS C code
+.EX
+#define _GNU_SOURCE
+#include <string.h>
+\&
+#include <nxt_unit.h>
+\&
+void
+request_handler(nxt_unit_request_info_t *req)
+{
+    int             rc;
+    nxt_unit_buf_t  *buf, *buf2;
+\&
+    rc = nxt_unit_response_init(req, 200, 1, strlen("Content\-Type")
+                                             + strlen("text/plain")
+                                             + strlen("Hello world!\en"));
+    if (rc != 0) {
+        goto fail;
+    }
+\&
+    rc = nxt_unit_response_add_field(req, "Content\-Type",
+                                          strlen("Content\-Type"),
+                                          "text/plain",
+                                          strlen("text/plain"));
+    if (rc != 0) {
+        goto fail;
+    }
+\&
+    rc = nxt_unit_response_add_content(req, "Hello world!\en",
+                                            strlen("Hello world!\en"));
+    if (rc != 0) {
+        goto fail;
+    }
+\&
+    rc = nxt_unit_response_send(req);
+    if (rc != 0) {
+        goto fail;
+    }
+\&
+    buf = nxt_unit_response_buf_alloc(req,
+                                      strlen("Some extra contents.\en"));
+    if (buf == NULL) {
+        rc = NXT_UNIT_ERROR;
+        goto fail;
+    }
+\&
+    buf2 = nxt_unit_response_buf_alloc(req,
+                                       strlen("But send this first.\en"));
+    if (buf2 == NULL) {
+        rc = NXT_UNIT_ERROR;
+        goto fail;
+    }
+\&
+    buf2\->free = mempcpy(buf2\->free, "But send this first.\en",
+                                     strlen("But send this first.\en"));
+    buf\->free  = mempcpy(buf\->free, "Some extra contents.\en",
+                                    strlen("Some extra contents.\en"));
+\&
+    rc = nxt_unit_buf_send(buf2);
+    if (rc != 0) {
+        goto fail;
+    }
+\&
+    rc = nxt_unit_buf_send(buf);
+    if (rc != 0) {
+        goto fail;
+    }
+\&
+    rc = nxt_unit_response_write(req, "And some more\en",
+                                      strlen("And some more\en"));
+    if (rc != 0) {
+        goto fail;
+    }
+\&
+fail:
+    nxt_unit_request_done(req, rc);
+}
+.EE
+.SH Copyright
+(C) 2017-2023, NGINX, Inc.
+.PP
+SPDX-License-Identifier: Apache-2.0
+.SH See also
+.MR nxt_unit_init 3 ,
+.MR nxt_unit_response_init 3 ,
+.MR nxt_unit_response_write 3 ,
+.MR unitd 8
+.PP
+.UR https://unit.nginx.org
+Website
+.UE
+.PP
+.UR https://mailman.nginx.org/mailman/listinfo/unit
+Mailing list
+.UE
+.PP
+.UR https://github.com/nginx/unit
+GitHub
+.UE
diff --git a/man3/nxt_unit_response_init.3 b/man3/nxt_unit_response_init.3
new file mode 100644
index 000000000..0b32559e6
--- /dev/null
+++ b/man3/nxt_unit_response_init.3
@@ -0,0 +1,85 @@
+.\" (C) 2023, NGINX, Inc.
+.\"
+.TH nxt_unit_response_init 3 (date) "NGINX Unit (unreleased)"
+.SH Name
+nxt_unit_response_init \- initialize response in Unit app
+.SH Library
+NGINX Unit library
+.RI ( libunit ", " -lunit )
+.SH Synopsis
+.nf
+.B #include <nxt_unit.h>
+.PP
+.BI "int nxt_unit_response_init(nxt_unit_request_info_t *" req ", uint16_t " status ,
+.BI "                           uint32_t " max_fields ,
+.BI "                           uint32_t " max_fields_size );
+.fi
+.SH Arguments
+.TP
+.I req
+Request object.
+.TP
+.I status
+HTTP status code.
+.TP
+.I max_fields
+Maximum number of HTTP header fields that will be added to the response.
+.TP
+.I max_fields_size
+Size of the buffer that will be used for the HTTP header fields.
+See
+.MR nxt_unit_response_add_field 3 .
+.SH Description
+.MR nxt_unit_response_init 3
+initializes a response to a request.
+.PP
+It sets the response status,
+and allocates the buffer necessary for the header fields.
+Any fields will need to fit in that buffer.
+The response content can also be fitted in that buffer,
+but extra buffers can be allocated for it later with
+.MR nxt_unit_response_buf_alloc 3 .
+.SH Return value
+0 on success,
+or a non-zero error code on error.
+.SH Errors
+Errors will be reported in the Unit debug log.
+.TP
+.B NXT_UNIT_ERROR
+.RS
+.PD 0
+.IP \[bu] 3
+Response already initialized.
+.IP \[bu]
+Response already sent.
+.IP \[bu]
+.MR nxt_unit_malloc 3
+failed.
+.PD
+.RE
+.SH Examples
+See
+.MR nxt_unit_response_add_field 3 .
+.SH Copyright
+(C) 2017-2023, NGINX, Inc.
+.PP
+SPDX-License-Identifier: Apache-2.0
+.SH See also
+.MR nxt_unit_init 3 ,
+.MR nxt_unit_response_add_field 3 ,
+.MR nxt_unit_response_add_content 3 ,
+.MR nxt_unit_response_send 3 ,
+.MR nxt_unit_response_buf_alloc 3 ,
+.MR unitd 8
+.PP
+.UR https://unit.nginx.org
+Website
+.UE
+.PP
+.UR https://mailman.nginx.org/mailman/listinfo/unit
+Mailing list
+.UE
+.PP
+.UR https://github.com/nginx/unit
+GitHub
+.UE
diff --git a/man3/nxt_unit_response_send.3 b/man3/nxt_unit_response_send.3
new file mode 100644
index 000000000..56788644b
--- /dev/null
+++ b/man3/nxt_unit_response_send.3
@@ -0,0 +1,88 @@
+.\" (C) 2023, NGINX, Inc.
+.\"
+.TH nxt_unit_response_send 3 (date) "NGINX Unit (unreleased)"
+.SH Name
+nxt_unit_response_send \- send response in Unit app
+.SH Library
+NGINX Unit library
+.RI ( libunit ", " -lunit )
+.SH Synopsis
+.nf
+.B #include <nxt_unit.h>
+.PP
+.BI "int nxt_unit_response_send(nxt_unit_request_info_t *" req );
+.fi
+.SH Arguments
+.TP
+.I req
+Request object.
+.SH Description
+.MR nxt_unit_response_send 3
+sends a response to a request.
+The response should have been previously crafted with
+.MR nxt_unit_response_add_field 3
+and
+.MR nxt_unit_response_add_content 3 .
+.PP
+If the
+.B Content-length
+header field is not present in the response,
+Unit will automatically add a
+.B Transfer-Encoding: chunked
+header.
+In that case,
+it is possible to call this function several times,
+and Unit will use chunks as appropriate for the contents.
+.PP
+This function tells
+.MR unitd 8
+that the response is ready to be sent,
+and puts it in the send queue.
+It doesn't really send it,
+and it may merge several response chunks into a single one
+if they accumulate in the buffer.
+.PP
+When the response has been completely sent,
+.MR nxt_unit_response_done 3
+should be called.
+.SH Return value
+0 on success,
+or a non-zero error code on error.
+.SH Errors
+Errors will be reported in the Unit debug log.
+.TP
+.B NXT_UNIT_ERROR
+.RS
+.PD 0
+.IP \[bu] 3
+Response not initialized yet.
+.IP \[bu]
+Response already sent.
+.PD
+.RE
+.SH Examples
+See
+.MR nxt_unit_response_add_field 3 .
+.SH Copyright
+(C) 2017-2023, NGINX, Inc.
+.PP
+SPDX-License-Identifier: Apache-2.0
+.SH See also
+.MR nxt_unit_init 3 ,
+.MR nxt_unit_response_init 3 ,
+.MR nxt_unit_response_add_field 3 ,
+.MR nxt_unit_response_add_content 3 ,
+.MR nxt_unit_response_buf_alloc 3 ,
+.MR unitd 8
+.PP
+.UR https://unit.nginx.org
+Website
+.UE
+.PP
+.UR https://mailman.nginx.org/mailman/listinfo/unit
+Mailing list
+.UE
+.PP
+.UR https://github.com/nginx/unit
+GitHub
+.UE
diff --git a/man3/nxt_unit_response_write.3 b/man3/nxt_unit_response_write.3
new file mode 100644
index 000000000..a9ca392b8
--- /dev/null
+++ b/man3/nxt_unit_response_write.3
@@ -0,0 +1,84 @@
+.\" (C) 2023, NGINX, Inc.
+.\"
+.TH nxt_unit_response_write 3 (date) "NGINX Unit (unreleased)"
+.SH Name
+nxt_unit_response_write
+\-
+write content of a response in Unit app
+.SH Library
+NGINX Unit library
+.RI ( libunit ", " -lunit )
+.SH Synopsis
+.nf
+.B #include <nxt_unit.h>
+.PP
+.BI "int nxt_unit_response_write(nxt_unit_request_info_t *" req ,
+.BI "                            const void " content [. size "], uint32_t " size );
+.fi
+.SH Arguments
+.TP
+.I req
+Request object.
+.TP
+.I content
+Content of the response.
+It's a buffer of
+.I size
+bytes.
+.SH Description
+.MR nxt_unit_response_buf_alloc 3
+allocates a buffer for a response to a request,
+or for a chunk of it.
+.PP
+.MR nxt_unit_buf_send 3
+sends and deallocates the buffer previously allocated with
+.MR nxt_unit_response_buf_alloc 3 .
+.SH Return value
+.TP
+.MR nxt_unit_response_buf_alloc 3
+A pointer to the allocated buffer on success,
+or NULL on error.
+.TP
+.MR nxt_unit_buf_send 3
+0 on success,
+or a non-zero error code on error.
+.SH Errors
+Errors will be reported in the Unit debug log.
+.TP
+.B NXT_UNIT_ERROR
+.RS
+.PD 0
+.IP \[bu] 3
+.I size
+was too big.
+.IP \[bu]
+Allocation failed.
+.IP \[bu]
+Failed to share the buffer with
+.MR unitd 8 .
+.PD
+.RE
+.SH Examples
+See
+.MR nxt_unit_response_buf_alloc 3 .
+.SH Copyright
+(C) 2017-2023, NGINX, Inc.
+.PP
+SPDX-License-Identifier: Apache-2.0
+.SH See also
+.MR nxt_unit_init 3 ,
+.MR nxt_unit_response_init 3 ,
+.MR nxt_unit_response_write 3 ,
+.MR unitd 8
+.PP
+.UR https://unit.nginx.org
+Website
+.UE
+.PP
+.UR https://mailman.nginx.org/mailman/listinfo/unit
+Mailing list
+.UE
+.PP
+.UR https://github.com/nginx/unit
+GitHub
+.UE
diff --git a/man3/nxt_unit_run.3 b/man3/nxt_unit_run.3
new file mode 100644
index 000000000..2de7d10a0
--- /dev/null
+++ b/man3/nxt_unit_run.3
@@ -0,0 +1,98 @@
+.\" (C) 2023, NGINX, Inc.
+.\"
+.TH nxt_unit_run 3 (date) "NGINX Unit (unreleased)"
+.SH Name
+nxt_unit_run \- run Unit app or app thread
+.SH Library
+NGINX Unit library
+.RI ( libunit ", " -lunit )
+.SH Synopsis
+.nf
+.B #include <nxt_unit.h>
+.PP
+.B enum {
+.B "    NXT_UNIT_OK,"
+.B "    NXT_UNIT_ERROR,"
+.B "    NXT_UNIT_AGAIN,"
+.B };
+.PP
+.BI "int nxt_unit_run(nxt_unit_ctx_t *" ctx );
+.fi
+.SH Arguments
+.TP
+.I ctx
+Thread or main context object for the application.
+See
+.MR nxt_unit_init 3
+and
+.MR nxt_unit_ctx_alloc 3 .
+.SH Description
+.MR nxt_unit_run 3
+runs the application or application thread,
+and puts it to work.
+.SH Return value
+0 on success,
+or an error code on error.
+.SH Errors
+Errors will be reported in the Unit debug log.
+.TP
+.B NXT_UNIT_ERROR
+.RS
+.PD 0
+.IP \[bu] 3
+.MR recvmsg 2
+failed.
+.IP \[bu]
+.MR sendmsg 2
+failed.
+.IP \[bu]
+.MR poll 2
+failed.
+.IP \[bu]
+.MR dup2 2
+failed.
+.IP \[bu]
+.MR nxt_unit_malloc 3
+failed.
+.IP \[bu]
+.I nxt_unit_init_t::callbacks.port_recv()
+failed.
+.IP \[bu]
+.I nxt_unit_init_t::callbacks.port_send()
+failed.
+.IP \[bu]
+Internal communication failure.
+.IP \[bu]
+Internal hash table failure.
+.PD
+.RE
+.TP
+.B NXT_UNIT_AGAIN
+Some resource was busy;
+try again.
+.SH Examples
+See
+.MR nxt_unit_init 3
+and
+.MR nxt_unit_ctx_alloc 3 .
+.SH Copyright
+(C) 2017-2023, NGINX, Inc.
+.PP
+SPDX-License-Identifier: Apache-2.0
+.SH See also
+.MR nxt_unit_init 3 ,
+.MR nxt_unit_ctx_alloc 3 ,
+.MR nxt_unit_done 3 ,
+.MR unitd 8
+.PP
+Website
+.UR https://unit.nginx.org
+.UE
+.PP
+Mailing list
+.UR https://mailman.nginx.org/mailman/listinfo/unit
+.UE
+.PP
+GitHub
+.UR https://github.com/nginx/unit
+.UE
diff --git a/man3/nxt_unit_sptr_get.3 b/man3/nxt_unit_sptr_get.3
new file mode 100644
index 000000000..2666d6e8b
--- /dev/null
+++ b/man3/nxt_unit_sptr_get.3
@@ -0,0 +1,91 @@
+.\" (C) 2023, NGINX, Inc.
+.\"
+.TH nxt_unit_sptr_get 3 (date) "NGINX Unit (unreleased)"
+.SH Name
+nxt_unit_sptr_set, nxt_unit_sptr_get \-
+serialized pointer; offset to self
+.SH Library
+NGINX Unit library
+.RI ( libunit ", " -lunit )
+.SH Synopsis
+.nf
+.B #include <nxt_unit.h>
+.PP
+.BI "void nxt_unit_sptr_set(nxt_unit_sptr_t *" sptr ", void *" ptr );
+.BI "void *nxt_unit_sptr_get(nxt_unit_sptr_t *" sptr );
+.PP
+.B "typedef union nxt_unit_sptr_u  nxt_unit_sptr_t;"
+.fi
+.PP
+.EX
+.B union nxt_unit_sptr_u {
+.B "    uint8_t   base[1];"
+.B "    uint32_t  offset;"
+.B }
+.EE
+.SH Arguments
+.TP
+.I sptr
+Serialized pointer.
+It represents a memory address as
+an offset to the address of the offset itself.
+.TP
+.I ptr
+Pointer to be serialized.
+.SH Description
+This type and helper functions are useful for
+having dynamically structured data
+in a single buffer.
+.TP
+.I nxt_unit_sptr_t
+The
+.I base
+array is used for representing the base to which the offset applies.
+It's not really used for reinterpreting the data in the union.
+The base is the address of the first element in the array,
+which is the same as the address of the union,
+and thus is also the same as the address of the offset.
+.IP
+The
+.I offset
+is really the only field actually accessed in this union.
+It points to the start of the data.
+.\".IP
+.\"This type could have been defined as a single offset integer,
+.\"without using unions or arrays,
+.\"but then it wouldn't be so clear that the offset points to
+.\"some data later in the same container structure.
+.TP
+.MR nxt_unit_sptr_set 3
+Set the offset in the serialized pointer
+to point to the data pointed to by
+.IR ptr .
+.TP
+.MR nxt_unit_sptr_get 3
+Get a pointer to the data referenced by the serialized pointer
+.IR sptr .
+.PP
+It is necessary to store pointers as offsets
+when sharing a buffer via inter-process communication.
+.SH Return value
+.MR nxt_unit_sptr_get 3
+returns a pointer to the data previously set by
+.MR nxt_unit_sptr_set 3 .
+.SH Errors
+None.
+.SH Copyright
+(C) 2017-2023, NGINX, Inc.
+.PP
+SPDX-License-Identifier: Apache-2.0
+.SH See also
+Website
+.UR https://unit.nginx.org
+.UE
+.PP
+Mailing list
+.UR https://mailman.nginx.org/mailman/listinfo/unit
+.UE
+.PP
+GitHub
+.UR https://github.com/nginx/unit
+.UE
diff --git a/scripts/LinuxManBook/LMBfront.roff b/scripts/LinuxManBook/LMBfront.roff
index fdf1a9820..9451ea5e9 100644
--- a/scripts/LinuxManBook/LMBfront.roff
+++ b/scripts/LinuxManBook/LMBfront.roff
@@ -14,20 +14,20 @@
 .sp .6i
 .ad r
 .ps 52
-\m[maroon]GNU/Linux\m[]
+\m[maroon]NGINX Unit\m[]
 .sp 18p
 .ps 16
 \f[BMB]THE MAN-PAGES BOOK\fP
 .sp 6i
 .ps 12
-\f[HB]Maintainers:\fP
+\f[HB]Programmers:\fP
 .sp 2p
 .ps 10
-\f[HB]Alejandro Colomar <alx@kernel.org> 2020 - present (5.09 - HEAD)
+\f[HB]Valentin V. Bartenev <vbartenev@gmail.com> 2020 - present (5.09 - HEAD)
 .brp
-Michael Kerrisk <mtk.manpages@gmail.com> 2004 - 2021    (2.00 - 5.13)
+Andrei Zeliankou <@.> 2004 - 2021    (2.00 - 5.13)
 .brp
-Andries Brouwer <aeb@cwi.nl> 1995 - 2004     (1.6  - 1.70)
+Max Romanov <@.> 1995 - 2004     (1.6  - 1.70)
 .brp
-Rik Faith 1993 - 1995     \0(1.0  - 1.5)\fP
+Igor Sysoev 1993 - 1995     \0(1.0  - 1.5)\fP
 .bp