The other mainstream language at the time was BASIC, comparable to the way PHP is viewed today by many.
And with the advent of the 32 bit x86 era GCC and djgpp as well as early Linux systems really unlocked a lot of power. Before then you'd have to have access to a VAX or a fancy workstation to get that kind of performance out of PC hardware. It's funny how long it took for the 386 to become fully operational, many years after it was launched you had to jump through all kinds of hoops to be able to use the system properly, whereas on a 68K based system costing a tiny fraction that was considered completely normal.
How did people see Fortran back then - nowadays it's seen as outdated but fast, but was it seen as interesting, and what drove you to seek it out?
Other side question if it's okay, I keep seeing references to VAXen around historical documents and usenet posts from the 80s and 90s, what made them special compared to other hardware you had back then?
The reason that library existed in FORTRAN was that it had a native 'vector' type and allowed for decent optimization on the proper hardware (ie: multiply and accumulate) which we did not have. But the library had been validated and was approved for civil engineering purposes, porting it over would have been a ton of work and would not have served any purpose, besides it would have required recertification.
As for VAXen: A VAX 11/780 is a 32 bit minicomputer, something the size of a large fridge (though later there were also smaller ones and today you could probably stick one on a business card). It had a - for the time - a relatively large amount of memory, and was a timesharing system, in other words, multiple people used the same computer via terminals.
They weren't special per se other than that a whole raft of programmers from those days cut their teeth on them either because they came across them in universities or because they worked with them professionally. They were 'affordable' in the sense that you did not need to be a multinational or a bank in order to buy one, think a few hundred thousand $ (which was still quite a fortune back then).
I had occasional access to one through the uni account of a friend, but never did any serious work with them. The first powerful machine I got my hands on was the Atari ST, which had a 68K chip in it and allowed the connection of a hard drive. Together those two things really boosted my capabilities, suddenly I had access to a whole 512K of RAM (later 1M) and some serious compute. Compared to a time shared VAX it was much better, though the VAX had more raw power.
Concurrent to that I programmed on mainframes for a bank for about a year or so, as well as on the BBC Micro computer (6502 based) and the Dragon 32 (a UK based Color Computer clone).
Fun times. Computing back then was both more and less accessible than it is today. More because the machines were so much simpler, less because you didn't have the internet at your disposal to look stuff up.
The 386 was hampered by backwards compatibility with the weird memory architecture for the 286 and 8086, IIRC. 68Ks were just soooo much easier.
I remember making a bootloader for my own OS using TurboC that somehow had to fish four files from a minix based filesystem and dump them in memory at certain addresses and then switch to flat mode and start executing the kernel which would then initialize the system properly. That was some really weird mixed mode voodoo to switch back and forth between protected mode and real mode to be able to both use BIOS calls to fetch blocks from disk and to be able to park the data in the right spots in contiguous memory.
Very tricky stuff to get right, it took me forever before I had the first indication that something was executing after the inevitable hail Mary jump to the first instruction in the loaded kernel. But I got it to work. I actually had a guitar footpedal hooked to the reset button because it took me too many dives under the desk to recover from a crash. That was a very slow development cycle without any chance of debugging. At some point I had 8 leds hooked up to the printer port to use some 'out' opcodes to tell me where I had gotten to in the code. Poor mans emulator :)
I remember meeting people who could not wrap their heads around the idea that function parameters weren't all passed by reference. The idea of recursion would have caused them to detonate.
It's really dependent on which field you're in. Not all scientific computing requires a beefy computer, but for a very long time it (and I guess LISP) dominated scientific computing. That said, I think it's a very good point to bring up the network effect of using C - if I need to hire a developer in 1985, it's probably easier to find someone with industry (not academic) experience who knows C than it is to find someone who knows Fortran.
I do kinda prefer Fortran to C though, it's so much cleaner to do math in. Maybe somewhere there's an alternate universe where IBM invented C and Bell invented Fortran to win the popularity war.