{FEC} Updated existing documents (#855)

Update documents

docs/API-functions.md

@@ -969,7 +969,7 @@ connection parties.
 #### SRT_REJ_FILTER
 
 The `SRTO_PACKETFILTER` option has been set differently on both connection
-parties (NOTE: this flag may not exist yet in this version).
+parties.
 
 
 ### srt_rejectreason_str

docs/API.md

@@ -687,6 +687,17 @@ dropped
 
 ---
 
+| OptName               | Since | Binding | Type   | Units  | Default  | Range   |
+| --------------------- | ----- | ------- | ------ | ------ | -------- | ------- |
+| `SRTO_PACKETFILTER`   | 1.4.0 | pre     | string |        |          | [...512]| 
+
+- **[SET]** - Set up the packet filter. The string must match appropriate syntax
+for packet filter setup.
+
+For details, see [Packet Filtering & FEC](packet-filtering-and-fec.md).
+
+---
+
 | OptName             | Since | Binding | Type   | Units | Default  | Range    |
 | ------------------- | ----- | ------- | ------ | ----- | -------- | -------- |
 | `SRTO_PASSPHRASE`   | 0.0.0 | pre     | string |       | [0]      | [10..79] |

srtcore/common.h

@@ -594,10 +594,10 @@ class CSeqNo
    /// and with the statement that only the sign of the result matters.
    /// That is, it returns a negative value if seq1 < seq2,
    /// positive if seq1 > seq2, and zero if they are equal.
-   /// The only tolerable use of this function is only when you
-   /// compare two values and it works faster than seqoff, however
+   /// The only correct application of this function is when you
+   /// compare two values and it works faster than seqoff. However
    /// the result's meaning is only in its sign. DO NOT USE THE
-   /// VALUE for any other purpose and its not meant to be the
+   /// VALUE for any other purpose. It is not meant to be the
    /// distance between two sequence numbers.
    ///
    /// Example: to check if (seq1 %> seq2): seqcmp(seq1, seq2) > 0.