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865 :: Terminal Width

• DarkBlue (orginal) [2015-02-13T08:37:18+01:00] view original

  I want to test for terminal width on linux like so:

  import os,osproc,parseutils,strutils
  var terminalwidth:int
  terminalwidth = execCmd("tput cols")
  echo "TerminalWidth : ",terminalwidth
  Run

  However there maybe is only the errorcode returned, rather then the output. The output echoed on the terminal is correct and changes if I adjust the terminal width. Using execCmdEx , I get a tuple back, but it always contains [80,0] , which is wrong.

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• Araq (orginal) [2015-02-13T09:21:42+01:00] view original

  So? Do you think we have some special code in execCmdEx that lies to you? Or maybe tput is simply broken, like everything else in Unix?

  http://stackoverflow.com/questions/14308166/tput-cols-doesnt-work-properly-in-a-script

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• DarkBlue (orginal) [2015-02-13T09:58:23+01:00] view original

  :) No, it does not lie , I looked into the source, but it does not yet say what I hoped for either. I try to get the same result as from my python script.

  #!/usr/bin/env python
  import subprocess
  command = ['tput', 'cols']
  def get_terminal_width():
     try:
         width = int(subprocess.check_output(command))
     except OSError as e:
         print("Invalid Command '{0}': exit status ({1})".format(
             command[0], e.errno))
     except subprocess.CalledProcessError as e:
         print("Command '{0}' returned non-zero exit status: ({1})".format(
             command, e.returncode))
     else:
         return width
  
  def main():
     width = get_terminal_width()
     if width:
         print(width)
  
  if __name__ == "__main__":
     main()
  Run

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• def (orginal) [2015-02-13T11:29:32+01:00] view original

  The reason for this is that Nim's osproc redirects the input. For tput cols to work the input must stay stdin. I needed something like this a few days ago as well, so I guess osproc should be extended so that you can select which streams to redirect and which to keep to the standard ones.

  Alternatively you can use the lower level C functions (which don't seem to be standardized at all...):

  type WinSize = object
    row, col, xpixel, ypixel: cushort
  
  const TIOCGWINSZ = 0x5413
  
  proc ioctl(fd: cint, request: culong, argp: pointer)
    {.importc, header: "<sys/ioctl.h>".}
  
  var size: WinSize
  ioctl(0, TIOCGWINSZ, addr size)
  echo size
  echo size.col
  Run

  This echoes:

  (row: 24, col: 89, xpixel: 712, ypixel: 336)
  89
  Run

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