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Not all systems support the classicteeprogram for splitting output pipes to multiple destinations. This command sends the output from someprog to/tmp/outputand to the mail pipe beyond.
% someprog | tee /tmp/output | Mail -s 'check this' user@host.org
This program helps not only users who aren't on Unix systems and don't
have a regular tee. It also helps those who are, because it offers
features not found on other version of tee.
The four flag arguments are-ito ignore interrupts,-ato append to output files,-ufor unbuffered output, and-nto omit copying the output on to standard out.
Veamos algunas ejecuciones:
lhp@nereida:~/Lgroovy/files$ echo 'hola LHP' |./tctee.groovy file1 file2
hola LHP
lhp@nereida:~/Lgroovy/files$ cat file1 file2
hola LHP
hola LHP
lhp@nereida:~/Lgroovy/files$ echo 'hola mundo' |./tctee.groovy -n '| cat -n' file2
1 hola mundo
lhp@nereida:~/Lgroovy/files$ cat file2
hola mundo
lhp@nereida:~/Lgroovy/files$ echo 'hola mundo' |./tctee.groovy -n '| cat -n' '>>file2'
1 hola mundo
lhp@nereida:~/Lgroovy/files$ cat file2
hola mundo
hola mundo
generaciondecodigos@nereida:~/src/groovy/files$ cat -n tctee.groovy
1 #!/usr/bin/env groovy
2 class MultiStream {
3 private targets
4 private ignoreErrors
5 MultiStream(List targets, ignore) {
6 this.targets = targets
7 ignoreErrors = ignore
8 }
9 def println(String content) {
10 targets.each{
11 try {
12 it?.write(content.bytes)
13 } catch (Exception ex) {
14 if (!ignoreErrors) throw ex
15 targets -= it
16 it?.close()
17 }
18 }
19 }
20 def close() { targets.each{ it?.close() } }
21 }
22
23 class TeeTarget {
24 private filename
25 private stream
26 private p
27
28 TeeTarget(String name, append, buffered, ignore) {
29 if (name.startsWith('>>')) {
30 createFileStream(name[2..-1],true,buffered,ignore)
31 } else if (name.startsWith('|')) {
32 createProcessReader(name[1..-1])
33 } else {
34 createFileStream(name,append,buffered,ignore)
35 }
36 }
37
38 TeeTarget(OutputStream stream) { this.stream = stream }
39
40 def write(bytes) { stream?.write(bytes) }
41 def close() { stream?.close() }
42
43 private createFileStream(name, append, buffered, ignore) {
44 filename = name
45 def fos
46 try {
47 fos = new FileOutputStream(name, append)
48 } catch (Exception ex) {
49 if (ignore) return
50 }
51 if (!buffered) stream = fos
52 else stream = new BufferedOutputStream(fos)
53 }
54 private createWriter(os) {new PrintWriter(new BufferedOutputStream(os))}
55 private createReader(is) {new BufferedReader(new InputStreamReader(is))}
56 private createPiperThread(br, pw) {
57 Thread.start{
58 def next
59 while((next = br.readLine())!=null) {
60 pw.println(next)
61 }
62 pw.flush(); pw.close()
63 }
64 }
65 private createProcessReader(name) {
66 def readFromStream = new PipedInputStream()
67 def r1 = createReader(readFromStream)
68 stream = new BufferedOutputStream(new PipedOutputStream(readFromStream))
69 p = Runtime.runtime.exec(name)
70 def w1 = createWriter(p.outputStream)
71 createPiperThread(r1, w1)
72 def w2 = createWriter(System.out)
73 def r2 = createReader(p.inputStream)
74 createPiperThread(r2, w2)
75 }
76 }
77
78 targets = []
79 append = false; ignore = false; includeStdout = true; buffer = true
80 (0..<args.size()).each{
81 arg = args[it]
82 if (arg.startsWith('-')) {
83 switch (arg) {
84 case '-a': append = true; break
85 case '-i': ignore = true; break
86 case '-n': includeStdout = false; break
87 case '-u': buffer = false; break
88 default:
89 println "usage: tee [-ainu] [filenames] ..."
90 System.exit(1)
91 }
92 } else targets += arg
93 }
94 targets = targets.collect{ new TeeTarget(it, append, buffer, ignore) }
95 if (includeStdout) targets += new TeeTarget(System.out)
96 def tee = new MultiStream(targets, ignore)
97 def stdin = new BufferedReader(new InputStreamReader(System.in))
98
99 stdin.eachLine { line ->
100 tee.println("$line\n")
101 }
102 tee.close()