linux - Escape echo output from redirecting to a file -

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• redirect copy of stdout log file within bash script itself 8 answers

i have script following

function long_proc() {     #script1 generate output1     #script2 generate output2     .... }  long_proc > /tmp/debug.log 

my requirement complete log should divert /tmp/debug.log output of script2 should go stdout log file.

can 1 me?

so think want do.

to keep output on stdout go file

long_proc(){      exec 4>&1     #redirect fd4(currently nothing hopefully) stdout      exec 1>&3     #redirect stdout fd3(also unused)     #note have 5 more choose if in use.       echo log     #script1 generate output1      echo log , stdout | tee >(cat - >&4)     #script1 generate output2     # tee subproc cat data fd4 pointing stdout     #the tee'd data goes fd3      exec 1>&4     # set fd1 stdout      exec 4>&-     #close fd4  }  long_proc 3> log #send fd3 log, stdout untouched , whatever want. 

so redirect output fd3, piped log. tee stdout want in stdout.

benefit of can pipe like

long_proc 3> log | sed 's/^/piped , /'