ade@clark.uucp (Adrian Miranda) (07/04/90)
I believe that shared text means that if a program is invoked more than once, there will only be one copy of it in memory. Does ESIX (or any version of UNIX for the 386) support this? If so, are any special options to the compiler needed to get it? Adrian Miranda uunet!clark!ade
cpcahil@virtech.uucp (Conor P. Cahill) (07/04/90)
In article <1990Jul4.070251.7143@clark.uucp> ade@clark.uucp (Adrian Miranda) writes: >I believe that shared text means that if a program is invoked more >than once, there will only be one copy of it in memory. >Does ESIX (or any version of UNIX for the 386) support this? If >so, are any special options to the compiler needed to get it? ALL current unix systems (BSD and System V) share text segments without needing any special compiler options. NOTE that only the text segments are shared. Data segments are not shared. For example "size /bin/sh" reports: 46692 + 4076 + 1036 = 51804 This tells me that 46K is shared text, and the rest (5K) is not shared date. Yet another note: size only reports base text and size requirements, it does not include any other memory that will be used by the program like malloc space, shared memory, etc. There are some systems that turn "shared text" off if the executable has been loaded with the -g flag (this is the mechanism that those systems use to allow the text section to be written when setting breakpoints). The 386 Unix packages are not in this group. -- Conor P. Cahill (703)430-9247 Virtual Technologies, Inc., uunet!virtech!cpcahil 46030 Manekin Plaza, Suite 160 Sterling, VA 22170