Imported Upstream version 7.40.0

[platform/upstream/curl.git] / docs / libcurl / curl_easy_pause.3

diff --git a/docs/libcurl/curl_easy_pause.3 b/docs/libcurl/curl_easy_pause.3
index 7debfd8..0f6ad5a 100644 (file)
--- a/docs/libcurl/curl_easy_pause.3
+++ b/docs/libcurl/curl_easy_pause.3
@@ -5,7 +5,7 @@
 .\" *                            | (__| |_| |  _ <| |___
 .\" *                             \___|\___/|_| \_\_____|
 .\" *
-.\" * Copyright (C) 1998 - 2013, Daniel Stenberg, <daniel@haxx.se>, et al.
+.\" * Copyright (C) 1998 - 2014, Daniel Stenberg, <daniel@haxx.se>, et al.
 .\" *
 .\" * This software is licensed as described in the file COPYING, which
 .\" * you should have received as part of this distribution. The terms
@@ -31,15 +31,17 @@ curl_easy_pause - pause and unpause a connection
 Using this function, you can explicitly mark a running connection to get
 paused, and you can unpause a connection that was previously paused.
 
-A connection can be paused by using this function or by letting the read
-or the write callbacks return the proper magic return code
+A connection can be paused by using this function or by letting the read or
+the write callbacks return the proper magic return code
 (\fICURL_READFUNC_PAUSE\fP and \fICURL_WRITEFUNC_PAUSE\fP). A write callback
 that returns pause signals to the library that it couldn't take care of any
 data at all, and that data will then be delivered again to the callback when
 the writing is later unpaused.
 
-NOTE: while it may feel tempting, take care and notice that you cannot call
-this function from another thread.
+While it may feel tempting, take care and notice that you cannot call this
+function from another thread. To unpause, you may for example call it from the
+progress callback (\fICURLOPT_PROGRESSFUNCTION(3)\fP), which gets called at
+least once per second, even if the connection is paused.
 
 When this function is called to unpause reading, the chance is high that you
 will get your write callback called before this function returns.
@@ -52,11 +54,11 @@ connection. The following bits can be used:
 .IP CURLPAUSE_RECV
 Pause receiving data. There will be no data received on this connection until
 this function is called again without this bit set. Thus, the write callback
-(\fICURLOPT_WRITEFUNCTION\fP) won't be called.
+(\fICURLOPT_WRITEFUNCTION(3)\fP) won't be called.
 .IP CURLPAUSE_SEND
 Pause sending data. There will be no data sent on this connection until this
 function is called again without this bit set. Thus, the read callback
-(\fICURLOPT_READFUNCTION\fP) won't be called.
+(\fICURLOPT_READFUNCTION(3)\fP) won't be called.
 .IP CURLPAUSE_ALL
 Convenience define that pauses both directions.
 .IP CURLPAUSE_CONT
@@ -65,6 +67,10 @@ Convenience define that unpauses both directions
 CURLE_OK (zero) means that the option was set properly, and a non-zero return
 code means something wrong occurred after the new state was set.  See the
 \fIlibcurl-errors(3)\fP man page for the full list with descriptions.
+.SH LIMITATIONS
+The pausing of transfers does not work with protocols that work without
+network connectivity, like FILE://. Trying to pause such a transfer, in any
+direction, will cause problems in the worst case or an error in the best case.
 .SH AVAILABILITY
 This function was added in libcurl 7.18.0. Before this version, there was no
 explicit support for pausing transfers.