---
name: "dacshttp"
section: "1"
platform: "linux"
package: "dacs"
version: "1.4.40-2"
release: "Debian 10 (Buster)"
platforms: ["linux"]
url: "https://new.carta.tech/dacshttp"
---

# dacshttp(1)

perform an HTTP/HTTPS request

## NAME

dacshttp - perform an HTTP/HTTPS request

## SYNOPSIS

**dacshttp** \[**-get** \| **-post** \| **-delete** \| **-head** \| **-options** \| **-soptions** \| **-put**\] \[**-ll** *log\_level*\]\
 \[**-prompt**\] \[**-v**\] \[**--version**\] \[\[**-ct** *string*\] \| \[**--content-type** *string*\]\]\
 \[{**-header** *name* *value*}...\] \[**-headers** *filename*\] \[**-body** *filename*\] \[**-ih**\]\
 \[**-user-agent** *string*\] \[{**-p** *name* *value*}...\] \[**-proto** *version-num*\]\
 \[**-proxy** *proxyhost*:*proxyport*\] \[**-proxymatch** *hostname*\[:*port*\] *proxyhost*:*proxyport*\]\
 \[**-f** *name* *filename*\] \[{**-cookies** *filename*}...\] \[**-ah**\]\
 \[**-ssl** *command-line*\] \[**-ssl-flags** *flags*\]\
 \[**-u** *userinfo*\] \[**-U** *proxy-userinfo*\] *uri*

## DESCRIPTION

This program is part of the **DACS** suite. It is a stand-alone program that neither accepts the usual **DACS** command line options (**dacsoptions**\[1\]) nor accesses any **DACS** configuration files.

This general-purpose utility sends an HTTP/HTTPS request for *uri* to a web server and prints the reply to its standard output.

**dacshttp** will automatically follow redirects according to **RFC 2616**\[2\] and up to a compile-time maximum, unless the **-prompt** flag is given. A non-standard extension is that a redirect to a non-absolute URI is interpreted in a manner compatible with most browsers.

In versions 1.4.27b and earlier, this command was called **http**.

**Note**\

**DACS** can issue its own HTTP requests, such as from **dacs\_authenticate** to an external authentication module. This HTTP functionality is provided by the same support code that the **dacshttp** command uses, and therefore much of the following information applies to these internally generated requests also (e.g., **HTTP\_PROG**\[3\], **SSL\_PROG**\[4\], **SSL\_PROG\_ARGS**\[5\], **SSL\_PROG\_CA\_CRT**\[6\], **SSL\_PROG\_CLIENT\_CRT**\[7\], **VFS**\[8\]).

## OPTIONS

The HTTP GET method is used by default, but some flags implicitly select a different method (e.g., **-f** and **-p**). One of the following flags can be used to explicitly specify the HTTP method, provided it is compatible with the other options:

- **-get**

  Use the GET method (the default).

- **-post**

  Use the POST method.

- **-head**

  Use the HEAD method.

- **-put**

  Use the PUT method.

- **-delete**

  Use the DELETE method.

- **-options**

  Use the OPTIONS method.

- **-soptions**

  Use the OPTIONS method but ignore anything that follows the authority component of *uri* and instead use the special case "\*" request URI that means that the request applies to the server itself rather than to a particular resource.

These command line flags are also recognized:

- **-ah**

  If cookies (credentials) are to be sent (see **-cookies**), use an Authorization header rather than a Cookie header.

- **-body** *filename*

  Read the message body from *filename*. It is assumed that the body has already been appropriately formatted for the request's content type.

- **-cookies** *filename*

  Obtain cookies from *filename*, one per line, to send with the request using the Cookie header. Multiple cookies are separated using a semi-colon, which follows the **Netscape spec**\[9\]. Alternatively, multiple cookies can be combined on a single line, separated by either a semi-colon or a comma (following **RFC 2109**\[10\], **RFC 2965**\[11\] or **RFC 6265**\[12\]). This argument may be repeated.

- **-ct** *string* **--content-type** *string*

  Set the Content-Type request-header to *string*. If the request has an entity-body, the default Content-Type is application/x-www-form-urlencoded; if the request does not have an entity-body, by default the Content-Type request-header is not set.

**-f** *name* *filename*

Passes and encodes the contents of *filename* as the value for name. By default, the POST method will be used, although PUT and OPTIONS can be selected. If *filename* is "**-**", the standard input is read; this form can only be used once on the command line. This argument may be repeated.

**-header** *name* *value*

This flag, which may be repeated, causes the HTTP header *name*: *value* to be sent with the request. Neither *name* nor *value* are checked in any way.

**Note**\
 This will not override headers required or implied by other command line flags, and can result in multiple instances of the same header. For example, the following flags are not equivalent:

```
-header User-Agent foo
-user-agent foo
```

The former case will send the User-Agent header twice.

- **-headers** *filename*

  Read additional message headers from *filename*, one per line, and send them with the request (refer to the **-header** flag). This flag may be repeated.

- **-ih**

  Include the HTTP response headers in the output. They are terminated by a blank line. The status line is labelled "Status-Line".

- **-ll** *log\_level*

  Set the debugging output level to *log\_level* (see **[dacs(1)](/dacs/1.md)**\[13\]). The default level is warn, and the **-v** flag bumps the level to debug or trace.

**-p** *name* *value*

Passes and encodes name=value as part of the entity-body. By default, the POST method will be used, although PUT and OPTIONS can be selected. This argument may be repeated.

- **-prompt**

  Prompt the user for permission to proceed after certain events, such as receiving a redirect; the response is affirmative only if it is "yes" or "y". If this option is not specified, the affirmative action will automatically be taken.

- **-proto** *version-num*

  Function in compliance with *version-num* of the HTTP protocol (e.g., 1.0).

- **-proxy** *proxyhost*:*proxyport*

  Forward all HTTP requests (except for those that match a **-proxymatch** flag) to the proxy server at *proxyport* (a numeric port number or recognized service name) on *proxyhost* (a domain name or IP address). Proxying is not fully supported by **dacshttp**, but it will connect to the specified proxy server instead of the server implied by *uri*.

**-proxymatch** *hostname*\[:*port*\] *proxyhost*:*proxyport*

If *hostname* matches the host specified in *uri*, proxy the HTTP request through *proxyhost* (a domain name or IP address) at *proxyport* (a numeric port number or recognized service name). If *port* is not given, it is assumed to be 80 (for the http scheme) or 443 (for the https scheme). Matching is done by resolving *hostname* to an IP address (if necessary) and comparing it to the effective IP address that is specified by *uri*. This flag is given priority over the **-proxy** flag, so it can be used to override a default proxy server.

**Note**\
 This option is not implemented. The SSL/TLS flags apply to *all* connections; this is probably a bug.

- **-ssl** *command-line*

  This flag indicates that HTTPS (i.e, HTTP over an SSL/TLS connection) is to be used, regardless of the scheme specified by *uri*. Because **dacshttp** does not directly include SSL/TLS functionality, it uses pipes to communicate with an external program that provides the SSL/TLS connection. The **[sslclient(1)](/sslclient/1.md)**\[14\] command is strongly recommended for this purpose (version 3.26 of **[stunnel(1)](/stunnel/1.md)** and **stunnel3**, which comes with some releases of **stunnel-4.x**, might also work).

  The *command-line* is a complete shell command line that will be used to run the program as a filter. For example, this argument might look like either of:

  ```
  -ssl "/usr/local/dacs/bin/sslclient example.com:443"
  -ssl "/usr/local/bin/stunnel -c -r example.com:443"
  ```

  If the **-ssl** argument is absent but the *uri* argument uses the https scheme, **dacshttp** will still try to use SSL/TLS. It will attempt to use **[sslclient(1)](/sslclient/1.md)**\[14\] and assume it is in its default location. If the **-ssl** argument is present but specifies only one string, that string is assumed to be the path to **[sslclient(1)](/sslclient/1.md)**\[14\]. The first example below will run **[sslclient(1)](/sslclient/1.md)**\[14\] from /tmp/sslclient to connect to port 443 at example.com; the second example has the same effect but will run **[sslclient(1)](/sslclient/1.md)**\[14\] from its default location:

  ```
  % dacshttp -ssl "/tmp/sslclient" https://example.com
  % dacshttp https://example.com
  ```

- **-ssl-flags** *flags*

  If SSL/TLS operation is enabled but the **-ssl** flag is absent or did not simply specify a pathname, append *flags* to the list of arguments to be passed to the external SSL/TLS provider; when the **-ssl** flag specifies more than one argument, this flag is ignored. The *flags* string is a space-separated list of arguments. This flag may be repeated.

  For example, in this example **dacshttp** will invoke **sslclient** with the two arguments *-sm* and *bobo.example.com*:

  ```
  % dacshttp -ssl-flags "-sm bobo.example.com" https://example.com
  ```

  If a wildcard server certificate is used, it may be necessary to explicitly match all hosts within a specific domain:

  ```
  % dacshttp -ssl-flags "-sm .*\.example\.com" https://example.com
  ```

  **Important**\
   When called by **dacshttp**, error messages produced by **sslclient** may be lost. If you encounter problems with SSL/TLS operation, work with **[sslclient(1)](/sslclient/1.md)**\[14\] to ensure that an SSL/TLS connection can be established, or to determine and resolve the problem. If you discover that **sslclient** requires command line flags for proper operation, you will need to make sure that **dacshttp** passes those flags to it.

- **-user-agent** *string*

  Set the User-Agent request-header to *string*. If not provided, this string will have the prefix "DACS-http/", followed by a **DACS** release identifier (example: "DACS-http/1.4.1").

- **-u** *userinfo* **--user** *userinfo*

  Send an Authorization header conforming to the HTTP Basic Authentication scheme (**RFC 2617**\[15\]). The *userinfo* consists of a username followed by a colon followed by the user's password. Since the password will be visible, use this flag with caution.

- **-U** *proxy-userinfo* **--proxyuser** *proxy-userinfo*

  Send a Proxy-Authorization header conforming to the HTTP Basic Authentication scheme (**RFC 2617**\[15\]). The *proxy-userinfo* consists of a username, a colon, and then a password for the proxy server. Since the password will be visible, use this flag with caution.

- **-v**

  Increase the level of debugging output. This will cause response headers to be displayed, for example. The flag may be repeated.

- **--version**

  Print version information to stderr, then exit immediately.

The *uri* argument is the URL to invoke. It may include a query string suffix (even if HTTP POST is selected). Though not recommended because it is not secure, the *uri* may include a userinfo component (**RFC 2617**\[15\]).

It is an error to attempt to send more than one Authorization header.

Whether selected implicitly or explicitly, the command line must specify exactly one of the HTTP methods.

Request headers specified using the **-header** or **-headers** flags are sent in the order in which the flags appear on the command line. If they are read from a file, there ordering is maintained.

## EXAMPLES

The following will retrieve **RFC 2616**\[2\] and save it in rfc2616.txt:

```
% dacshttp "http://www.rfc-editor.org/rfc/rfc2616.txt" > rfc2616.txt
```

This will do a GET on the given URL, passing the query string *foo=baz*, and writing the result to stdout:

```
% dacshttp "https://example.com/cgi-bin/dacs/dacs_prenv?foo=baz"
```

This will do a POST on the given URL, passing two arguments:

```
% dacshttp -p foo baz -p bar zork https://example.com/cgi-bin/dacs/dacs_prenv
```

This will make an HTTP GET method request over SSL/TLS to the given URL:

```
% dacshttp -ssl "/usr/local/dacs/bin/sslclient example.com:443" \
    https://example.com/cgi-bin/dacs/dacs_prenv
```

These two commands are equivalent. They submit a request associated with username julia and password herpasswd, which causes an Authorization header conforming to the HTTP Basic Authentication scheme (**RFC 2617**\[15\]) to be sent:

```
% dacshttp http://julia:herpasswd@example.com
% dacshttp -u julia:herpasswd http://example.com
```

## DIAGNOSTICS

The program exits 0 if everything was fine, 1 if an error occurred.

## BUGS

It can sometimes be a useful tool, but this program's primary purpose is for developing and testing **DACS** core functionality. There are many readily-available and better HTTP clients.

Use of an SSL/TLS provider other than **[sslclient(1)](/sslclient/1.md)**\[14\] is officially deprecated. **dacshttp** should not require an external program to provide SSL/TLS functionality. Recent development makes it doubtful that any other program will function properly with **dacshttp**.

**dacshttp** is only a partial implementation of **RFC 2616**\[2\]. It only talks HTTP (no other URI schemes are supported). Received cookies are discarded. Authentication via **RFC 2617**\[15\] is only partially implemented: a single username and password to authenticate the user submitting the request and/or a single username and password to gain access to a proxy server can be specified to be sent with the request. No client-side caching of any kind is performed.

## SEE ALSO

**[sslclient(1)](/sslclient/1.md)**\[14\], **[lynx(1)](/lynx/1.md)**\[16\], **[curl(1)](/curl/1.md)**\[17\], **Wget(1)**\[18\], **RFC 1738**\[19\], **RFC 2396**\[20\], **RFC 2616**\[2\], **RFC 3986**\[21\]

## AUTHOR

Distributed Systems Software (**www.dss.ca**\[22\])

## COPYING

Copyright © 2003-2014 Distributed Systems Software. See the **LICENSE**\[23\] file that accompanies the distribution for licensing information.

## NOTES

- 1\.

  dacsoptions

  http://dacs.dss.ca/man/dacs.1.html#dacsoptions

- 2\.

  RFC 2616

  http://www.rfc-editor.org/rfc/rfc2616.txt

- 3\.

  HTTP\_PROG

  http://dacs.dss.ca/man/dacs.conf.5.html#HTTP\_PROG

- 4\.

  SSL\_PROG

  http://dacs.dss.ca/man/dacs.conf.5.html#SSL\_PROG

- 5\.

  SSL\_PROG\_ARGS

  http://dacs.dss.ca/man/dacs.conf.5.html#SSL\_PROG\_ARGS

- 6\.

  SSL\_PROG\_CA\_CRT

  http://dacs.dss.ca/man/dacs.conf.5.html#SSL\_PROG\_CA\_CRT

- 7\.

  SSL\_PROG\_CLIENT\_CRT

  http://dacs.dss.ca/man/dacs.conf.5.html#SSL\_PROG\_CLIENT\_CRT

- 8\.

  VFS

  http://dacs.dss.ca/man/dacs.conf.5.html#VFS

- 9\.

  Netscape spec

  http://web.archive.org/web/20070805052634/http://wp.netscape.com/newsref/std/cookie\_spec.html

- 10\.

  RFC 2109

  http://www.rfc-editor.org/rfc/rfc2109.txt

- 11\.

  RFC 2965

  http://www.rfc-editor.org/rfc/rfc2965.txt

- 12\.

  RFC 6265

  http://www.rfc-editor.org/rfc/rfc6265.txt

- 13\.

  [dacs(1)](/dacs/1.md)

  http://dacs.dss.ca/man/dacs.1.html

- 14\.

  [sslclient(1)](/sslclient/1.md)

  http://dacs.dss.ca/man/sslclient.1.html

- 15\.

  RFC 2617

  http://www.rfc-editor.org/rfc/rfc2617.txt

- 16\.

  [lynx(1)](/lynx/1.md)

  http://lynx.isc.org

- 17\.

  [curl(1)](/curl/1.md)

  http://directory.fsf.org/All\_Packages\_in\_Directory/cURL.html

- 18\.

  Wget(1)

  http://www.gnu.org/software/wget/wget.html

- 19\.

  RFC 1738

  http://www.rfc-editor.org/rfc/rfc1738.txt

- 20\.

  RFC 2396

  http://www.rfc-editor.org/rfc/rfc2396.txt

- 21\.

  RFC 3986

  http://www.rfc-editor.org/rfc/rfc3986.txt

- 22\.

  www.dss.ca

  http://www.dss.ca

- 23\.

  LICENSE

  http://dacs.dss.ca/man/../misc/LICENSE