wait(1) 맨 페이지 - 윈디하나의 솔라나라

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wait(1)

wait(1)                          User Commands                         wait(1)



NAME
       wait - await process completion

SYNOPSIS
   /bin/sh
       wait [pid]...


   /bin/jsh /bin/ksh88 /usr/xpg4/bin/sh
       wait [pid]...


       wait [% jobid...]


   /bin/csh
       wait


   ksh
       wait [job...]


DESCRIPTION
       The  shell itself executes wait, without creating a new process. If you
       get the error message cannot fork,too many  processes,  try  using  the
       wait  command  to  clean  up your background processes. If this doesn't
       help, the system process table is probably full or you  have  too  many
       active  foreground processes. There is a limit to the number of process
       IDs associated with your login, and to the number the system  can  keep
       track of.


       Not all the processes of a pipeline with three or more stages are chil‐
       dren of the shell, and thus cannot be waited for.

   /bin/sh, /bin/jsh
       Wait for your background process whose process ID is pid and report its
       termination  status.  If  pid  is  omitted,  all your shell's currently
       active background processes are waited for and the return  code  is  0.
       The  wait utility accepts a job identifier, when Job Control is enabled
       (jsh), and the argument, jobid, is preceded by a percent sign (%).


       If pid is not an active process ID, the wait  utility  returns  immedi‐
       ately and the return code is 0.

   csh
       Wait for your background processes.

   ksh88
       When  an  asynchronous  list is started by the shell, the process ID of
       the last command in each element of the asynchronous list becomes known
       in the current shell execution environment.


       If  the  wait  utility  is invoked with no operands, it waits until all
       process IDs known to the invoking shell have terminated and  exit  with
       an exit status of 0.


       If one or more pid or jobid operands are specified that represent known
       process IDs (or jobids), the wait utility waits until all of them  have
       terminated.  If  one  or  more pid or jobid operands are specified that
       represent unknown process IDs (or jobids), wait treats them as if  they
       were  known  process  IDs (or jobids) that exited with exit status 127.
       The exit status returned by the wait utility is the exit status of  the
       process requested by the last pid or jobid operand.


       The  known  process  IDs are applicable only for invocations of wait in
       the current shell execution environment.

   ksh
       wait with no operands, waits until all jobs known to the invoking shell
       have  terminated. If one or more job operands are specified, wait waits
       until all of them have completed. Each job can be specified as  one  of
       the following:

       number      number refers to a process ID.


       -number     number refers to a process group ID.


       %number     number refers to a job number


       %string     Refers to a job whose name begins with string


       %?string    Refers to a job whose name contains string


       %+          Refers to the current job
       %%

       %-          Refers to the previous job



       If  one  ore  more job operands is a process id or process group id not
       known by the current shell environment, wait treats each of them as  if
       it were a process that exited with status 127.

OPERANDS
       The following operands are supported:

       pid      The  unsigned  decimal  integer  process  ID of a command, for
                which the utility is to wait for the termination.


       jobid    A job control job ID  that  identifies  a  background  process
                group  to  be  waited  for. The job control job ID notation is
                applicable only for invocations of wait in the  current  shell
                execution  environment, and only on systems supporting the job
                control option.


USAGE
       On most implementations, wait is a shell built-in. If it is called in a
       subshell  or separate utility execution environment, such as one of the
       following,

         (wait)
         nohup wait ...
         find . -exec wait ... \;




       it returns immediately because there is no known process  IDs  to  wait
       for in those environments.

EXAMPLES
       Example 1 Using A Script To Identify The Termination Signal


       Although  the exact value used when a process is terminated by a signal
       is unspecified, if it is known that a signal terminated  a  process,  a
       script  can  still  reliably  figure out which signal is using kill, as
       shown by the following (/bin/ksh88 and /usr/xpg4/bin/sh):


         sleep 1000&
         pid=$!
         kill -kill $pid
         wait $pid
         echo $pid was terminated by a SIG$(kill -l $(($?−128))) signal.



       Example 2 Returning The Exit Status Of A Process


       If the following sequence of commands is run in less  than  31  seconds
       (/bin/ksh88 and /usr/xpg4/bin/sh):


         sleep 257 | sleep 31 &

         jobs -l %%




       then  either  of  the following commands returns the exit status of the
       second sleep in the pipeline:


         wait <pid of sleep 31>
         wait %%



ENVIRONMENT VARIABLES
       See environ(5) for descriptions of the following environment  variables
       that affect the execution of wait: LANG, LC_ALL, LC_CTYPE, LC_MESSAGES,
       and NLSPATH.

EXIT STATUS
   ksh
       The following exit values are returned by the wait built-in in ksh:

       0      wait was invoked with no operands. All processes  known  by  the
              invoking process have terminated.


       127    job  is  a process id or process group id that is unknown to the
              current shell environment.


ATTRIBUTES
       See attributes(5) for descriptions of the following attributes:




       tab()  box;  cw(2.75i)  |cw(2.75i)  lw(2.75i)   |lw(2.75i)   ATTRIBUTE
       TYPEATTRIBUTE  VALUE _ Availabilitysystem/core-os _ Interface Stabil‐
       ityCommitted _ StandardSee standards(5).


SEE ALSO
       csh(1), jobs(1), ksh(1), ksh88(1), pwait(1), sh(1), attributes(5), env‐
       iron(5), standards(5)



SunOS 5.11                        12 Jul 2011                          wait(1)
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