list-logins 1 administrator commands nosh list-logins login listing tool list-logins --field name --time-format formatstring --no-init line(s) list-logins is a tool for listing login information. Its output is machine-parseable and suitable for console-flat-table-viewer1 with 1 header line and --format tabbed or awk1 with -F'\t'. The line command-line arguments are a filter set that is matched against the line names, enabling the selection of individual login records. If there are no line arguments, the entire list is output, unfiltered. It is not an error for a filter item not to match a line. The --field command-line option specifies a list of fields by name. What exactly the fields are varies from operating system to operating system. There is a basic common set: line, user, host, and time. The --time-format command-line option specifies an alternative display format to be employed for all time fields, formatstring, in the form employed by the strftime3 library function. The --no-init command-line option has no effect on most BSDs, where the concept is meaningless. On Linux-based operating systems, it excludes INIT_PROCESS and LOGIN_PROCESS records, login-process1 and the programs that it is compatible with. With modern systems with modern system managers, this option is either meaningless or moot. The output format is variable-length records terminated by LF containing TAB-separated fields. Fields are output as if passed through the BSD vis3 library function. They are thus unambiguously machine-parseable, because any whitespace in the field itself is encoded by vis3. After separating out an individual field, its contents can (for example) be decoded in shell script using the unvis1 utility (which is supplied by FreeBSD). The field names are transformed to uppercase for the initial header record. This command uses list-logins to produce similar output to who1 with its -H option. $ list-logins --field name --field line --field time --field host | > awk '{ if (1 == NR) print; else printf "%s\t%s\t%s\t(%s)\n",$1,$2,$3,$4; }' | > unvis This command uses list-logins to display a continually updated table similar to who1 with its -H option. $ while list-logins --field pid --field name --field line --field time --field host | > awk '{ if ( 2 > NR ) printf "\f%s\n",$0; else printf "%s\t%s\t%s\t%s\t%s\t(%s)\n",$1,$2,$3,$4,$5,$6; }' > do > sleep 5 > done | > console-flat-table-viewer --format tabbed --header-count 1 Jonathan de Boyne Pollard