info > COLCRT

📄 NAME

colcrt - filter nroff output for CRT previewing

🚀 Quick Reference

📋 SYNOPSIS

colcrt [options] [file ...]

📝 DESCRIPTION

colcrt provides virtual half-line and reverse line feed sequences for terminals without such capability, and on which overstriking is destructive. Half-line characters and underlining (changed to dashing `-') are placed on new lines in between the normal output lines.

⚙️ OPTIONS

• -, --no-underlining — 🔇 Suppress all underlining. This option is especially useful for previewing allboxed tables from tbl(1).
• -2, --half-lines — ↔️ Causes all half-lines to be printed, effectively double spacing the output. Normally, a minimal space output format is used which will suppress empty lines. The program never suppresses two consecutive empty lines, however. The -2 option is useful for sending output to the line printer when the output contains superscripts and subscripts which would otherwise be invisible.
• -V, --version — ℹ️ Display version information and exit.
• -h, --help — ❓ Display help text and exit.

📜 HISTORY

The colcrt command appeared in 3.0BSD.

🐛 BUGS

• Should fold underlines onto blanks even with the '-' option so that a true underline character would show.
• Can’t back up more than 102 lines.
• General overstriking is lost; as a special case '|' overstruck with '-' or underline becomes '+'.
• Lines are trimmed to 132 characters.
• Some provision should be made for processing superscripts and subscripts in documents which are already double-spaced.

💡 EXAMPLES

A typical use of colcrt would be:

tbl exum2.n | nroff -ms | colcrt - | more

🔗 SEE ALSO

col(1), more(1), nroff(1), troff(1), ul(1)

🐞 REPORTING BUGS

For bug reports, use the issue tracker at https://github.com/karelzak/util-linux/issues.

📦 AVAILABILITY

The colcrt command is part of the util-linux package which can be downloaded from Linux Kernel Archive <https://www.kernel.org/pub/linux/utils/util-linux/>.