variable substitution) in describing the

 

arguments. On Unix systems, you can control

 

which shell is used with the SHELL environment

 

variable. GDB uses the C shell (/usr/bin/csh).

 

See “Arguments To Your Program” (page 41).

environment.

Your program inherits its environment from

 

GDB. However, you can use the GDB commands

 

set environment and unset environment

 

to change parts of the environment that affect

 

your program. See“Program Environment”

 

(page 41).

working directory.

Your program inherits its working directory from

 

GDB. You can set the GDB working directory

 

with the cd command in GDB. See“Working

 

directory” (page 43).

standard input and output.

Your program as default uses the same device

 

for standard input and standard output as GDB

 

is using. You can redirect input and output in

 

the run command line, or you can use the tty

 

command to set a different device for your

40 Running Programs Under GDB