diff options
Diffstat (limited to 'guix/build/syscalls.scm')
-rw-r--r-- | guix/build/syscalls.scm | 29 |
1 files changed, 28 insertions, 1 deletions
diff --git a/guix/build/syscalls.scm b/guix/build/syscalls.scm index 90cacc760b..7a1bad7331 100644 --- a/guix/build/syscalls.scm +++ b/guix/build/syscalls.scm @@ -22,13 +22,15 @@ #:use-module (srfi srfi-1) #:use-module (ice-9 rdelim) #:use-module (ice-9 match) + #:use-module (ice-9 ftw) #:export (errno MS_RDONLY MS_REMOUNT MS_BIND MS_MOVE mount - umount)) + umount + processes)) ;;; Commentary: ;;; @@ -153,4 +155,29 @@ constants from <sys/mount.h>." (when update-mtab? (remove-from-mtab target)))))) +(define (kernel? pid) + "Return #t if PID designates a \"kernel thread\" rather than a normal +user-land process." + (let ((stat (call-with-input-file (format #f "/proc/~a/stat" pid) + (compose string-tokenize read-string)))) + ;; See proc.txt in Linux's documentation for the list of fields. + (match stat + ((pid tcomm state ppid pgrp sid tty_nr tty_pgrp flags min_flt + cmin_flt maj_flt cmaj_flt utime stime cutime cstime + priority nice num_thread it_real_value start_time + vsize rss rsslim + (= string->number start_code) (= string->number end_code) _ ...) + ;; Got this obscure trick from sysvinit's 'killall5' program. + (and (zero? start_code) (zero? end_code)))))) + +(define (processes) + "Return the list of live processes." + (sort (filter-map (lambda (file) + (let ((pid (string->number file))) + (and pid + (not (kernel? pid)) + pid))) + (scandir "/proc")) + <)) + ;;; syscalls.scm ends here |