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Ps command different behaviour

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Operating Systems Linux Red Hat Ps command different behaviour
# 1  
Old 09-08-2016
Ps command different behaviour
Hi Experts,

ps command behavior in Redhat is such that it outputs all the output(of long lengths). In Unix the ps command output was limited to only 80 chars. In that if you pipe its output to another command hen the 80 chars restriction wouldn't be there. This 80 char limitation will only be there for the screen output.

Is there any property/setup file for ps command on redhat which we may tweak to curtail the output to some specific characters?

There is an option --cols n which can curtail the output to n specific chars. But if we use this and pipe to another command, the another command will only get n chars as input from ps command.

My regards,
Albert
# 2  
Old 09-08-2016
From man ps:

Code:
       args        COMMAND   command with all its arguments as a string.
                             Modifications to the arguments may be shown.  The
                             output in this column may contain spaces.  A
                             process marked <defunct> is partly dead, waiting
                             to be fully destroyed by its parent.  Sometimes
                             the process args will be unavailable; when this
                             happens, ps will instead print the executable
                             name in brackets.  (alias cmd, command).  See
                             also the comm format keyword, the -f option, and
                             the c option.
                             When specified last, this column will extend to
                             the edge of the display.  If ps can not determine
                             display width, as when output is redirected
                             (piped) into a file or another command, the
                             output width is undefined (it may be 80,
                             unlimited, determined by the TERM variable, and
                             so on).  The COLUMNS environment variable or
                             --cols option may be used to exactly determine
                             the width in this case.  The w or -w option may
                             be also be used to adjust width.

So if ps isn't abiding by your terminal width, be sure the COLUMNS variable is set to a sane value in the user environment and exported, etc.
# 3  
Old 09-12-2016
Quote:
Originally Posted by Corona688
From man ps:

Code:
       args        COMMAND   command with all its arguments as a string.
                             Modifications to the arguments may be shown.  The
                             output in this column may contain spaces.  A
                             process marked <defunct> is partly dead, waiting
                             to be fully destroyed by its parent.  Sometimes
                             the process args will be unavailable; when this
                             happens, ps will instead print the executable
                             name in brackets.  (alias cmd, command).  See
                             also the comm format keyword, the -f option, and
                             the c option.
                             When specified last, this column will extend to
                             the edge of the display.  If ps can not determine
                             display width, as when output is redirected
                             (piped) into a file or another command, the
                             output width is undefined (it may be 80,
                             unlimited, determined by the TERM variable, and
                             so on).  The COLUMNS environment variable or
                             --cols option may be used to exactly determine
                             the width in this case.  The w or -w option may
                             be also be used to adjust width.

So if ps isn't abiding by your terminal width, be sure the COLUMNS variable is set to a sane value in the user environment and exported, etc.


Thanks but its not working, changed the COLUMNS variable. One thing which works is command line option of --cols which is not desirable as already stated by me in my original question. The value of COLUMNS is 168 but I see that ps command is showing output of much higher width.
# 4  
Old 09-12-2016
Did you just change the columns variable or actually export it? Show me exactly what you did, word for word, letter for letter, keystroke for keystroke.
# 5  
Old 09-12-2016
you can try resize.
Are you looking for a particular column from ps (e.g. cpu, command etc)? you can specifying them with the -o option(s).
# 6  
Old 09-12-2016
Quote:
Originally Posted by Corona688
Did you just change the columns variable or actually export it? Show me exactly what you did, word for word, letter for letter, keystroke for keystroke.
Hi Corona, it worked but not fully, if we pipe the output of this ps command to another command, such as grep, the grep wont get the full output of ps command which it would have got if COLUMNS var would not be set to our value

My regards,
Albert
# 7  
Old 09-12-2016
Which OS are you running?
Code:
uname -a
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