todd@narnia.ecs.rpi.edu (R. Lindsay Todd) (06/28/90)
I have a program that uses popen and pclose. If the program has a controlling tty, the commands started by popen work correctly. However, if there is no controlling tty, it seems like popen never even starts /bin/sh. Oh yes, this is true under both Ultrix 3.1 and SunOS 4.0.3, the only systems I've been able to try this with. There is nothing in the man pages I have that indicate that popen must have a controlling tty. Is this some unwritten standard "feature" of popen, or is it a buggy implementation? -- R. Lindsay Todd, Systems Programmer ECS, Rensselaer Polytechnic Institute, Troy, NY 12180-3590 Internet: todd@narnia.ecs.rpi.edu
gwyn@smoke.BRL.MIL (Doug Gwyn) (06/28/90)
In article <YQJ$'7_@rpi.edu> todd@narnia.ecs.rpi.edu (R. Lindsay Todd) writes: >There is nothing in the man pages I have that indicate that popen must have >a controlling tty. Is this some unwritten standard "feature" of popen, or >is it a buggy implementation? Maybe it's a bug in the application? popen() does not require a controlling tty; neither should the shell that it invokes. Unless somebody has been mucking around with the system software, something else must be going on.