exec(1)               MPE/iX Shell and Utilities               exec(1)
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  NAME
       exec -- execute a command in place of the current shell

  SYNOPSIS
       exec [command_line]

  DESCRIPTION
       The argument to exec is a command_line for another command.  exec
       runs this command without creating a new process.  Some people
       picture this as overlaying the command on top of the currently
       executing shell.  When the command exits, control returns to the
       parent of the shell.

       Input and output redirections are valid in the command_line. You
       can modify the input and output descriptors of the shell by giv-
       ing only input and output redirections in the command.  For
       example,

          exec 2>errors

       redirects the standard error stream to errors in all subsequent
       commands run by the shell.

       If you do not specify a command_line, exec simply returns a suc-
       cessful exit status.

  DIAGNOSTICS
       If you specify command_line, exec does not return to the shell.
       Instead, the shell exits with the exit status of command_line or
       one of the following exit status values:

       1-125 A redirection error occurred.

       126   The command in command_line was found but it was not an
             executable utility.

       127   The given command_line could not be executed because the
             command could not be found in the current PATH.

       If you did not specify command_line, exec returns with an exit
       value of zero.

  Messages
       Because this utility is built into the MPE/iX Shell, see the
       sh(1) man page for a complete list of error messages that you may
       receive when using it.

  PORTABILITY
       POSIX.2.  x/OPEN Portability Guide 4.0.  All UNIX systems.

  NOTE
       This is a special built-in command of the shell.

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  exec(1)               MPE/iX Shell and Utilities               exec(1)
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  MPE/iX NOTES
       For information on how the current MPE/iX implementation may
       affect the operation of this utility, see Appendix A, MPE/iX
       Implementation Considerations.

  SEE ALSO
       sh(1)

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