pid(n) Tcl Built-In Commands pid(n)______________________________________________________________________________NAMEpid - Retrieve process identifiers
SYNOPSISpid ?fileId?
_________________________________________________________________DESCRIPTION
If the fileId argument is given then it should normally refer to a
process pipeline created with the open command. In this case the pid
command will return a list whose elements are the process identifiers
of all the processes in the pipeline, in order. The list will be empty
if fileId refers to an open file that is not a process pipeline. If no
fileId argument is given then pid returns the process identifier of the
current process. All process identifiers are returned as decimal
strings.
EXAMPLE
Print process information about the processes in a pipeline using the
SysV ps program before reading the output of that pipeline:
set pipeline [open "| zcat somefile.gz | grep foobar | sort -u"]
# Print process information
exec ps -fp [pid $pipeline] >@stdout
# Print a separator and then the output of the pipeline
puts [string repeat - 70]
puts [read $pipeline]
close $pipeline
SEE ALSOexec(n), open(n)KEYWORDS
file, pipeline, process identifier
Tcl 7.0 pid(n)
