v0.2.4

README.md

@@ -83,6 +83,17 @@ to be continued...
 
 ## Examples
 
+**Attention**
+
+1. The CSV parser requires all the lines have same number of fields/columns.
+ Even lines with spaces will cause error.
+2. By default, csvtk think your files have header row, if not, use `-H`.
+3. By default, lines starting with `#` will be ignored, if the header row
+ starts with `#`, please assign `-C` another rare symbol, e.g. `&`.
+4. By default, csvtk handles CSV files, use `-t` for tab-delimited files.
+
+Examples
+
 1. Select fields/columns (`cut`)
 
     - By index: `csvtk cut -f 1,2`

csvtk/cmd/csv.go

@@ -96,7 +96,9 @@ func (csvReader *CSVReader) Run() {
 				csvReader.Ch <- CSVRecordsChunk{id, chunkData[0:i], err}
 				break
 			}
-
+			if record == nil {
+				continue
+			}
 			chunkData[i] = record
 			i++
 			if i == csvReader.chunkSize {

csvtk/cmd/root.go

@@ -34,13 +34,22 @@ var RootCmd = &cobra.Command{
 	Short: "Another cross-platform, efficient and practical CSV/TSV toolkit",
 	Long: `Another cross-platform, efficient and practical CSV/TSV toolkit
 
-Version: 0.2.3
+Version: 0.2.4
 
 Author: Wei Shen <[email protected]>
 
 Documents  : http://shenwei356.github.io/csvtk
 Source code: https://github.com/shenwei356/csvtk
 
+Attention:
+
+  1. The CSV parser requires all the lines have same number of fields/columns.
+     Even lines with spaces will cause error.
+  2. By default, csvtk think your files have header row, if not, use "-H".
+  3. By default, lines starting with '#' will be ignored, if the header row
+     starts with '#', please assign "-C" another rare symbol, e.g. '$'.
+  4. By default, csvtk handles CSV files, use "-t" for tab-delimited files.
+
 `,
 }
 
@@ -60,7 +69,8 @@ func init() {
 	RootCmd.PersistentFlags().StringP("delimiter", "d", ",", `delimiting character of the input CSV file`)
 	RootCmd.PersistentFlags().StringP("out-delimiter", "D", ",", `delimiting character of the input CSV file`)
 	// RootCmd.PersistentFlags().StringP("quote-char", "q", `"`, `character used to quote strings in the input CSV file`)
-	RootCmd.PersistentFlags().StringP("comment-char", "C", `#`, `commment character for start of line in the input CSV file`)
+	RootCmd.PersistentFlags().StringP("comment-char", "C", `#`, "lines starting with commment-character will be ignored. "+
+		`if your header row starts with '#', please assign "-C" another rare symbol, e.g. '$'`)
 	RootCmd.PersistentFlags().BoolP("lazy-quotes", "l", false, `if given, a quote may appear in an unquoted field and a non-doubled quote may appear in a quoted field`)
 
 	RootCmd.PersistentFlags().BoolP("tabs", "t", false, `specifies that the input CSV file is delimited with tabs. Overrides "-d"`)

doc/docs/download.md

@@ -6,9 +6,9 @@
 
 ## Current Version
 
-- [csvtk v0.2.3](https://github.com/shenwei356/csvtk/releases/tag/v0.2.3)
-    - add flag `--colnames` to `cut`
-    - flag `-f` (`--fields`) of `join` supports single value now
+- [csvtk v0.2.4](https://github.com/shenwei356/csvtk/releases/tag/v0.2.4)
+    - fix bug of handling comment lines
+    - add some notes before using csvtk
 
 ## Installation
 
@@ -32,6 +32,9 @@ You can also add the directory of the executable file to environment variable
 
 ## Previous Versions
 
+- [csvtk v0.2.3](https://github.com/shenwei356/csvtk/releases/tag/v0.2.3)
+    - add flag `--colnames` to `cut`
+    - flag `-f` (`--fields`) of `join` supports single value now
 - [csvtk v0.2.2](https://github.com/shenwei356/csvtk/releases/tag/v0.2.2)
     - add flag `--keep-unmathed` to `join`
 - [csvtk v0.2](https://github.com/shenwei356/csvtk/releases/tag/v0.2)

doc/docs/usage.md

@@ -1,19 +1,39 @@
 # Usage and Examples
 
+## Before use
+
+**Attention**
+
+1. The CSV parser requires all the lines have same number of fields/columns.
+ Even lines with spaces will cause error.
+2. By default, csvtk think your files have header row, if not, use `-H`.
+3. By default, lines starting with `#` will be ignored, if the header row
+ starts with `#`, please assign `-C` another rare symbol, e.g. `&`.
+4. By default, csvtk handles CSV files, use `-t` for tab-delimited files.
+
 ## csvkit
 
 Usage
 
 ```
 Another cross-platform, efficient and practical CSV/TSV toolkit
 
-Version: 0.2.3
+Version: 0.2.4
 
 Author: Wei Shen <[email protected]>
 
 Documents  : http://shenwei356.github.io/csvtk
 Source code: https://github.com/shenwei356/csvtk
 
+Attention:
+
+  1. The CSV parser requires all the lines have same number of fields/columns.
+     Even lines with spaces will cause error.
+  2. By default, csvtk think your files have header row, if not, use "-H".
+  3. By default, lines starting with '#' will be ignored, if the header row
+     starts with '#', please assign "-C" another rare symbol, e.g. '&'.
+  4. By default, csvtk handles CSV files, use "-t" for tab-delimited files.
+
 Usage:
   csvtk [command]
 
@@ -22,7 +42,7 @@ Available Commands:
   cut         select parts of fields
   grep        grep data by selected fields with patterns/regular expressions
   inter       intersection of multiple files
-  join         join multiple CSV files by selected fields
+  join        join multiple CSV files by selected fields
   mutate      create new column from selected fields by regular expression
   rename      rename column names
   rename2     rename column names by regular expression
@@ -36,16 +56,18 @@ Available Commands:
 
 Flags:
   -c, --chunk-size int         chunk size of CSV reader (default 50)
-  -C, --comment-char string    commment character for start of line in the input CSV file (default "#")
+  -C, --comment-char string    lines starting with commment-character will be ignored. if your header row starts with '#', please assign "-C" another rare symbol, e.g. '&' (default "#")
   -d, --delimiter string       delimiting character of the input CSV file (default ",")
   -l, --lazy-quotes            if given, a quote may appear in an unquoted field and a non-doubled quote may appear in a quoted field
   -H, --no-header-row          specifies that the input CSV file does not have header row
-  -j, --num-cups int           number of CPUs to use (default value depends on your computer) (default 4)
+  -j, --num-cpus int           number of CPUs to use (default value depends on your computer) (default 4)
   -D, --out-delimiter string   delimiting character of the input CSV file (default ",")
   -o, --out-file string        out file ("-" for stdout, suffix .gz for gzipped out) (default "-")
   -T, --out-tabs               specifies that the output is delimited with tabs. Overrides "-D"
   -t, --tabs                   specifies that the input CSV file is delimited with tabs. Overrides "-d"
 
+Use "csvtk [command] --help" for more information about a command.
+
 ```
 
 ## stat