MPE/iX Shell and Utilities Reference Manual, Vol 1

expr(1) MPE/iX Shell and Utilities expr(1)
DIAGNOSTICS
Possible exit status values are:
0 The result of expression is true.
1 The result of expression is false.
2 An error occurred.
Messages
Message: divide by 0
Cause: You attempted to divide a number by 0.
Action: Do not divide numbers by 0.
Message: internal tree error
Cause: You specified an expression that expr was unable to evaluate, due to either
syntax errors or unusual complexity.
Action: Correct the syntax errors, or simplify the expression (perhaps by breaking it into
parts).
Message: no space for expression or string
Cause: There were not enough free system resources for expr to allocate for a string
or expression.
Action: Simplify the expression.
Message: non-numeric argument "string"
Cause: You specified a string argument with an operator that requires a numeric argu-
ment (that is, +, -, *, /,or%).
Action: Replace the string argument with a numeric argument.
Message: regular expression error "regexp"
Cause: An error occurred while processing the regular expression regexp.
Action: Check the regular expression.
Message: strcoll error, cannot malloc space.
Cause: There are not enough free system resources to allocate string space.
Action: Free up more resources.
PORTABILITY
POSIX.2. x/OPEN Portability Guide 4.0. All UNIX systems.
In the shell, let(1) largely supercedes this command.
match, substr, length, and index are undocumented on all UNIX systems, though
they do appear to exist there. They are extensions to the POSIX standard.
Commands and Utilities 1-221