HP XC System 2.x Software manual Mode --output=mode, Mode --input=mode, Mode --error=mode, Label

commands let you choose from among any of five I/O redirection alternatives (modes) that are explained in the next section.

-o mode (--output=mode)

The -ooption redirects standard output stdout for this job to mode, one of five alternative ways to display, capture, or subdivide the job’s I/O, explained in the next section. By default, srun collects stdout from all job tasks and line buffers it to the attached terminal.

-i mode (--input=mode)

The -ioption redirects standard input stdin for this job from mode, one of five alternative ways to display, capture, or subdivide the job’s I/O, explained in the next section. By default, srun redirects stdin from the attached terminal to all job tasks.

-e mode (--error=mode)

The -eoption redirects standard error stderr for this job to mode, one of five alternative ways to display, capture, or subdivide the job’s I/O, explained in the next section. By default, srun collects stderr from all job tasks and line buffers it to the attached terminal, just as with stdout. But you can request that srun handle standard output and standard error differently by invoking -eand -owith different redirection modes.

-l (--label)

The -loption prepends the remote task ID number to each line of standard output and standard error. By default, srun line buffers this I/O to the terminal (or to specified files) without any task labels. Options -land -uare mutually exclusive.

-u (--unbuffered)

The -uoption prevents line buffering of standard output from remote tasks (buffering is the srun default). Options -land -uare mutually exclusive.

6.4.6.2 I/O Redirection Alternatives

The srun I/O options -i(-input), -o(-output), and -e(-error), all take any of five I/O redirection alternatives (modes) as arguments. These arguments are explained in this section.

all

The all argument redirects stdout and stderr from all job tasks to srun (and hence to the attached terminal), and broadcasts stdin from srun (the terminal) to all remote tasks. This is srun’s default behavior for handling I/O.

none

The none argument redirects stdout and stderr from all job tasks to /dev/null (receives no I/O from any task) and sends no stdin to any task (closes stdin).

taskid

The taskid argument redirects to srun (and hence to the attached terminal) stdout and stderr from the single specified task whose relative ID is taskid, where the range for integer taskid starts at 0 (the first task) and runs through the total number of tasks in the current job step. This choice also redirects stdin from srun (the terminal) to this single specified task.

filename

The filename argument redirects stdout or stderr from all job tasks into a single file called filename, or broadcasts stdin from that same file to all remote tasks, depending upon the I/O command.

Using SLURM 6-9