Mainflux.mainflux/vendor/github.com/xo/terminfo/README.md

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# About terminfo [![GoDoc][1]][2]
Package `terminfo` provides a pure-Go implementation of reading information
from the terminfo database.
`terminfo` is meant as a replacement for `ncurses` in simple Go programs.
## Installing
Install in the usual Go way:
```sh
$ go get -u github.com/xo/terminfo
```
## Using
Please see the [GoDoc API listing][2] for more information on using `terminfo`.
```go
// _examples/simple/main.go
package main
import (
"bytes"
"fmt"
"log"
"os"
"os/signal"
"strings"
"sync"
"syscall"
"github.com/xo/terminfo"
)
func main() {
//r := rand.New(nil)
// load terminfo
ti, err := terminfo.LoadFromEnv()
if err != nil {
log.Fatal(err)
}
// cleanup
defer func() {
err := recover()
termreset(ti)
if err != nil {
log.Fatal(err)
}
}()
terminit(ti)
termtitle(ti, "simple example!")
termputs(ti, 3, 3, "Ctrl-C to exit")
maxColors := termcolors(ti)
if maxColors > 256 {
maxColors = 256
}
for i := 0; i < maxColors; i++ {
termputs(ti, 5+i/16, 5+i%16, ti.Colorf(i, 0, "█"))
}
// wait for signal
sigs := make(chan os.Signal, 1)
signal.Notify(sigs, syscall.SIGINT, syscall.SIGTERM)
<-sigs
}
// terminit initializes the special CA mode on the terminal, and makes the
// cursor invisible.
func terminit(ti *terminfo.Terminfo) {
buf := new(bytes.Buffer)
// set the cursor invisible
ti.Fprintf(buf, terminfo.CursorInvisible)
// enter special mode
ti.Fprintf(buf, terminfo.EnterCaMode)
// clear the screen
ti.Fprintf(buf, terminfo.ClearScreen)
os.Stdout.Write(buf.Bytes())
}
// termreset is the inverse of terminit.
func termreset(ti *terminfo.Terminfo) {
buf := new(bytes.Buffer)
ti.Fprintf(buf, terminfo.ExitCaMode)
ti.Fprintf(buf, terminfo.CursorNormal)
os.Stdout.Write(buf.Bytes())
}
// termputs puts a string at row, col, interpolating v.
func termputs(ti *terminfo.Terminfo, row, col int, s string, v ...interface{}) {
buf := new(bytes.Buffer)
ti.Fprintf(buf, terminfo.CursorAddress, row, col)
fmt.Fprintf(buf, s, v...)
os.Stdout.Write(buf.Bytes())
}
// sl is the status line terminfo.
var sl *terminfo.Terminfo
// termtitle sets the window title.
func termtitle(ti *terminfo.Terminfo, s string) {
var once sync.Once
once.Do(func() {
if ti.Has(terminfo.HasStatusLine) {
return
}
// load the sl xterm if terminal is an xterm or has COLORTERM
if strings.Contains(strings.ToLower(os.Getenv("TERM")), "xterm") || os.Getenv("COLORTERM") == "truecolor" {
sl, _ = terminfo.Load("xterm+sl")
}
})
if sl != nil {
ti = sl
}
if !ti.Has(terminfo.HasStatusLine) {
return
}
buf := new(bytes.Buffer)
ti.Fprintf(buf, terminfo.ToStatusLine)
fmt.Fprint(buf, s)
ti.Fprintf(buf, terminfo.FromStatusLine)
os.Stdout.Write(buf.Bytes())
}
// termcolors returns the maximum colors available for the terminal.
func termcolors(ti *terminfo.Terminfo) int {
if colors := ti.Num(terminfo.MaxColors); colors > 0 {
return colors
}
return int(terminfo.ColorLevelBasic)
}
```
[1]: https://godoc.org/github.com/xo/terminfo?status.svg
[2]: https://godoc.org/github.com/xo/terminfo