18.4.0 released Sep 25, 2023
Send file

Purpose: Send file to client.

send-file <file> [ headers \
    [ content-type <content type> ] \
    [ download [ <download> ] ] \
    [ etag [ <etag> ] ] \
    [ file-name <file name> ] \
    [ ( cache-control <cache control> ) | no-cache ] \
    [ status-id <status id> ] \
    [ status-text <status text> ] \
    [ custom <header name>=<header value> [ , ... ] ]

When a client requests download of a file, you can use send-file to provide <file>, which is its location on the server, and is either a full path or relative to the application home directory (see vv). Note however that you can never use dot-dot (i.e. "..") in <file> - this is a security measure to avoid path-traversal attacks. Thus the file name should never have ".." in it, and if it does, the program will error out and stop.
The following are subclauses that allow setting any custom header:
Any cookies set prior to send-file (see set-cookie and delete-cookie) will be sent along with the file to the web client.
To send a document back to the browser and show it, use send-file with the "show" clause:
send-file "/home/vely/files/myfile.jpg" headers content-type "image/jpg"

An example to display a PDF document:
char *pdf_doc="/home/mydir/myfile.pdf";
send-file pdf_doc headers content-type "application/pdf"

If you want to send a file to the client for download (with the dialog), use "download" clause. This way the document is not displayed but the "Save As" (or similar) window shows up, for example to download a "PDF" document:
send-file "/home/user/file.pdf" headers download content-type "application/pdf"

See also
See all

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