Martin,
Thank you for the pointers, I appreciate. Still not out of the woods
though ...
As a starting point, you need to find out what library you need to
link in to provide these symbols. Strategies to find that out are
1. setsockopt(2)
man setsockopt does not mention any libraries - guess that means it's
in libc
2. nm /usr/lib/*.a|grep setsockopt
$ nm /usr/lib/*.a |grep setsockopt setsockopt |
setsockopt | 0000000000000000 | U |
0000000000000008
setsockopt | 0000000000000000 | U |
0000000000000008
setsockopt | 0000000000000000 | U |
0000000000000008
setsockopt | 0000000000000000 | U |
0000000000000008
__setsockopt | 0000000000000000 | U |
0000000000000008
__setsockopt | 0000000000000000 | U |
0000000000000008
/usr/lib/libc.a[setsockopt.o]:
__setsockopt | 0000000000000016 | T |
0000000000000008
setsockopt | 0000000000000016 | T |
0000000000000008
__setsockopt | 0000000000000000 | U |
0000000000000008
__setsockopt | 0000000000000000 | U |
0000000000000008
/usr/lib/libc_r.a[setsockopt.o]:
__setsockopt | 0000000000000016 | T |
0000000000000008
setsockopt | 0000000000000016 | T |
0000000000000008
setsockopt | 0000000000000000 | U |
0000000000000008
setsockopt | 0000000000000000 | U |
0000000000000008
man nm says T means external text, so if I am reading correctly this
confirms setsockopt is in libc
3. try -lsocket
$ find /usr -name libsocket.a
$ find /usr -name libsocket.so
Also,
$ c++ -pthread -o python Modules/python.o libpython2.3.a -lsocket -lrt
-lm
/usr/bin/ld:
Can't locate file for: -lsocket
collect2: ld returned 1 exit status
On Sun, yes, it uses -lsocket and configure script figures that out.
Here's my little test program:
/*
* to help build python
* gcc -o s s.c
*/
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <unistd.h>
int
main(int argc, char *argv[])
{
int ss, s, clilen, n, i;
struct sockaddr_in cli_addr, serv_addr;
char buf[512];
if ( (ss = socket(AF_INET, SOCK_STREAM, 0)) < 0 )
{
perror("can't open socket");
exit(-1);
}
memset( &serv_addr, 0, sizeof(serv_addr));
serv_addr.sin_family = AF_INET;
serv_addr.sin_addr.s_addr = htonl(INADDR_ANY);
serv_addr.sin_port = htons(12345);
if ( bind( ss, (struct sockaddr *) &serv_addr, sizeof(serv_addr)) <
0 )
{
perror("can't bind to port\n");
exit(-1);
}
listen(ss, 2);
clilen = sizeof(cli_addr);
s = accept( ss, (struct sockaddr *) &cli_addr, &clilen);
if (s < 0)
{
perror("server accept error");
}
for ( i=1; ; i++)
{
memset( buf, 0, 512);
if ( (n=read(s, buf, 512)) == 0) break;
printf("%d th message: %s; length: %d \n", i, buf, n);
}
close(s);
(void) printf("Hello socket!\n");
exit(0);
}
Compiles and runs ... never have to specify any library to make socket
work:
$ gcc -o s s.c]$ ./s &
[1] 12491
$ netstat -a |grep 12345
tcp 0 0 *.12345 *.*
LISTEN
$ telnet 12345
Trying 0.0.48.57...
Perhaps comparing the succesful OSF1 V5.1 and failed OSF1 V4.0 buils
may help:
[V5.1]$ ./configure |grep socket
checking sys/socket.h usability... yes
checking sys/socket.h presence... yes
checking for sys/socket.h... yes
checking for socket in -lsocket... no
[V5.1]$ make |grep socket
building '_socket' extension
gcc -pthread -DNDEBUG -g -O3 -Wall -Wstrict-prototypes
-fno-strict-aliasing -I.
-I/dat0/ajb/app/edmond/src/buildSandbox/Python-2.3.4/./Include
-I/usr/local/include
-I/dat0/ajb/app/edmond/src/buildSandbox/Python-2.3.4/Include
-I/dat0/ajb/app/edmond/src/buildSandbox/Python-2.3.4 -c
/dat0/ajb/app/edmond/src/buildSandbox/Python-2.3.4/Modules/socketmodule.c
-o build/temp.osf1-V5.1-alpha-2.3/socketmodule.o
ld -shared -expect_unresolved *
build/temp.osf1-V5.1-alpha-2.3/socketmodule.o -L/usr/local/lib -o
build/lib.osf1-V5.1-alpha-2.3/_socket.so
[V5.1]$ find . -name _socket.so
../build/lib.osf1-V5.1-alpha-2.3/_socket.so
[V5.1]$ nm build/lib.osf1-V5.1-alpha-2.3/_socket.so |grep setsockopt
setsockopt | 0000000000000000 | U |
0000000000000000
setsockopt_doc | 0004398043894268 | d |
0000000000000000
setsockopt_doc:S1006=ar56;000000000000000000000000 ;000000000000000000000232;2
| 0004398043894268 | d | 0000000000000001
sock_setsockopt | 0004396970424912 | t |
0000000000000008
sock_setsockopt:f267 | 0004396970424912 | t |
0000000000000008
[V4.0]$ ./configure |grep socket
checking sys/socket.h usability... yes
checking sys/socket.h presence... yes
checking for sys/socket.h... yes
checking for socket in -lsocket... no
[V4.0]$ make |grep socket
building '_socket' extension
gcc -pthread -DNDEBUG -g -O3 -Wall -Wstrict-prototypes
-fno-strict-aliasing -I.
-I/u101/ajbddg/edmond/src/sandbox/Python-2.3.4/./Include
-I/usr/local/include
-I/u101/ajbddg/edmond/src/sandbox/Python-2.3.4/Include
-I/u101/ajbddg/edmond/src/sandbox/Python-2.3.4 -c
/u101/ajbddg/edmond/src/sandbox/Python-2.3.4/Modules/socketmodule.c -o
build/temp.osf1-V4.0-alpha-2.3/socketmodule.o
/u101/ajbddg/edmond/src/sandbox/Python-2.3.4/Modules/socketmodule.c:
In function `sock_accept':
/u101/ajbddg/edmond/src/sandbox/Python-2.3.4/Modules/socketmodule.c:1137:
warning: passing arg 3 of `accept' from incompatible pointer type
/u101/ajbddg/edmond/src/sandbox/Python-2.3.4/Modules/socketmodule.c:
In function `sock_getsockopt':
/u101/ajbddg/edmond/src/sandbox/Python-2.3.4/Modules/socketmodule.c:1361:
warning: passing arg 5 of `getsockopt' from incompatible pointer type
/u101/ajbddg/edmond/src/sandbox/Python-2.3.4/Modules/socketmodule.c:1379:
warning: passing arg 5 of `getsockopt' from incompatible pointer type
/u101/ajbddg/edmond/src/sandbox/Python-2.3.4/Modules/socketmodule.c:
In function `sock_getsockname':
/u101/ajbddg/edmond/src/sandbox/Python-2.3.4/Modules/socketmodule.c:1623:
warning: passing arg 3 of `getsockname' from incompatible pointer type
/u101/ajbddg/edmond/src/sandbox/Python-2.3.4/Modules/socketmodule.c:
In function `sock_getpeername':
/u101/ajbddg/edmond/src/sandbox/Python-2.3.4/Modules/socketmodule.c:1651:
warning: passing arg 3 of `getpeername' from incompatible pointer type
/u101/ajbddg/edmond/src/sandbox/Python-2.3.4/Modules/socketmodule.c:
In function `sock_recvfrom':
/u101/ajbddg/edmond/src/sandbox/Python-2.3.4/Modules/socketmodule.c:1898:
warning: passing arg 6 of `recvfrom' from incompatible pointer type
ld -shared -expect_unresolved *
build/temp.osf1-V4.0-alpha-2.3/socketmodule.o -L/usr/local/lib -o
build/lib.osf1-V4.0-alpha-2.3/_socket.so
*** WARNING: renaming "_socket" since importing it failed: Unresolved
symbol in build/lib.osf1-V4.0-alpha-2.3/_socket.so: _Esetsockopt
[V4.0]$ find . -name '_socket*'
../PCbuild/_socket.dsp
../build/lib.osf1-V4.0-alpha-2.3/_socket_failed.so
[V4.0]$ nm build/lib.osf1-V4.0-alpha-2.3/_socket_failed.so |grep
setsockopt
_Esetsockopt | 0000000000000000 | U |
0000000000000000
setsockopt_doc | 0004398043893924 | d |
0000000000000000
setsockopt_doc:S794=ar55;000000000000000000000000; 000000000000000000000232;2
| 0004398043893924 | d | 0000000000000008
sock_setsockopt | 0004396970422608 | t |
0000000000000008
sock_setsockopt:f238 | 0004396970422608 | t |
0000000000000008
I don't understand if the '_E' in '_Esetsockopt' is significant and/or
where it comes from, but that's one difference that strikes me.
[V4.0]$ grep setsockopt Modules/socketmodule.c|wc
11 39 498
[V4.0]$ grep _Esetsockopt Modules/socketmodule.c|wc
0 0 0
Thank you in advance for your help.
Edmond
