projects / unix-history / blame
| Commit | Line | Data |
|---|---|---|
| 312f5e46 | 1 | .\" @(#)col.1 6.2 (Berkeley) %G% |
| 803f9663 | 2 | .\" |
| ed25c019 | 3 | .TH COL 1 "" |
| 803f9663 KM |
4 | .AT 3 |
| 5 | .SH NAME | |
| 6 | col \- filter reverse line feeds | |
| 7 | .SH SYNOPSIS | |
| c42eaf6b KM |
8 | .B col |
| 9 | [ | |
| 312f5e46 | 10 | .B \-bfh |
| c42eaf6b | 11 | ] |
| 803f9663 KM |
12 | .SH DESCRIPTION |
| 13 | .I Col | |
| 14 | reads the standard input and writes the standard output. | |
| 15 | It performs the line overlays implied by reverse line | |
| 16 | feeds (ESC-7 in ASCII) | |
| 17 | and by forward and reverse half line feeds (ESC-9 and ESC-8). | |
| 18 | .I Col | |
| 19 | is particularly useful for filtering multicolumn | |
| 20 | output made with the `.rt' command of | |
| 21 | .I nroff | |
| 22 | and output resulting from use of the | |
| 23 | .IR tbl (1) | |
| 24 | preprocessor. | |
| 25 | .PP | |
| 26 | Although | |
| 27 | .I col | |
| 28 | accepts half line motions in its input, it normally does not | |
| 29 | emit them on output. | |
| 30 | Instead, text that would appear between lines is moved to the next lower | |
| 31 | full line boundary. | |
| 32 | This treatment can be suppressed by the | |
| 33 | .B \-f | |
| 34 | (fine) option; in this case | |
| 35 | the output from | |
| 36 | .I col | |
| 37 | may contain forward half line feeds (ESC-9), but will still never contain | |
| 38 | either kind of reverse line motion. | |
| 39 | .PP | |
| 40 | If the | |
| 41 | .B \-b | |
| 42 | option is given, | |
| 43 | .I col | |
| 44 | assumes that the output device in use is not capable of backspacing. | |
| 45 | In this case, if several characters are to appear in the same place, | |
| 46 | only the last one read will be taken. | |
| 47 | .PP | |
| 48 | The control characters SO (ASCII code 017), | |
| 49 | and SI (016) are assumed | |
| 50 | to start and end text in an alternate character set. | |
| 51 | The character set (primary or alternate) associated with each printing | |
| 52 | character read is remembered; on output, SO and SI characters are generated | |
| 53 | where necessary to maintain the correct treatment of each character. | |
| 54 | .PP | |
| 803f9663 | 55 | If the |
| 312f5e46 KM |
56 | .B \-h |
| 57 | option is given, | |
| 58 | .I col | |
| 59 | converts white space to tabs to shorten printing time. | |
| 803f9663 KM |
60 | .PP |
| 61 | All control characters are removed from the input except space, | |
| 62 | backspace, | |
| 63 | tab, return, newline, ESC (033) followed by one of 7, 8, 9, SI, SO, and VT | |
| 64 | (013). | |
| 65 | This last character is an alternate form of full reverse line feed, for | |
| 66 | compatibility with some other hardware conventions. | |
| 67 | All other non-printing characters are ignored. | |
| 68 | .SH "SEE ALSO" | |
| c42eaf6b | 69 | troff(1), tbl(1) |
| 803f9663 KM |
70 | .SH BUGS |
| 71 | Can't back up more than 128 lines. | |
| 72 | .br | |
| 73 | No more than 800 characters, including backspaces, on a line. |