Phil, I know this isn't something you'd look for, but if you want a full listing of interfaces for a library, you could check out a page like http://refspecs.freestandards.org/LSB_2.1.0/LSB-Core-generic/LSB-Core-generic/generic-lsb.html under the Alphabetical listing of interfaces. Who knows, might help. corey On 24 Aug 2005 18:01:42 -0700, Ian Lance Taylor <ian@xxxxxxxx> wrote: > carterp@xxxxxxxxxxxxx writes: > > > I was trying to compile a program that used a function from math.h and couldn't > > get it to work, until I found out that I needed to use "gcc -lm test.c", and > > #include <math.h> in the program wasn't enough. I know from the documentation > > that -lxxxx searches the library named xxxx when linking, but how do I know > > what library to name? I wouldn't have guessed that I need -lm when I'm using > > math.h, and I'm wondering what the chances are that I'll run into this problem > > again when I need some other library. I'm also using time.h in a program, but > > I only needed to use an #include statement, with nothing extra on the command > > line. > > This is not actually a gcc issue. It is a library issue. > > Normally the documentation for the library will tell you which > libraries you need to link against. For example, on NetBSD, "man > sqrt" starts with > LIBRARY > Math Library (libm, -lm) > > Unfortunately, the man pages for the math functions on GNU/Linux don't > seem to say this (at least not on Fedora Core 4). Ideally that would > be fixed in the library documentation. > > Ian >
