From: Mike Frysinger <vapier@xxxxxxxxxxxx> Make sure people don't try to rely on this when there are no guarantees the target process respects it. Signed-off-by: Mike Frysinger <vapier@xxxxxxxxxx> --- man5/proc.5 | 15 ++++++++++++++- 1 file changed, 14 insertions(+), 1 deletion(-) diff --git a/man5/proc.5 b/man5/proc.5 index 0a3503f99360..89a7c09ad5af 100644 --- a/man5/proc.5 +++ b/man5/proc.5 @@ -477,7 +477,7 @@ check; see .BR ptrace (2). .TP .I /proc/[pid]/environ -This file contains the environment for the process. +This file contains the initial environment for the process. The entries are separated by null bytes (\(aq\\0\(aq), and there may be a null byte at the end. Thus, to print out the environment of process 1, you would do: @@ -488,6 +488,19 @@ Thus, to print out the environment of process 1, you would do: .fi .in +Once a process starts modifying its environment +(e.g. by calling functions such as +.BR putenv (3) +or modifying the +.BR environ (7) +variable directly), +this file will not be kept up to date. + +Further, a process may change the memory this points to by calling +.BR prctl (2) +and using operations such as +.BR PR_SET_MM_ENV_START . + Permission to access this file is governed by a ptrace access mode .B PTRACE_MODE_READ_FSCREDS check; see -- 2.11.0 -- To unsubscribe from this list: send the line "unsubscribe linux-man" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
