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Operating Systems OS X (Apple) Generate a random number in a fully POSIX compliant shell, 'dash'... Post 303043172 by wisecracker on Monday 20th of January 2020 04:48:24 PM
Old 01-20-2020
Hi MadeInGermany...
Although there is a workaround this is an edge case:
Code:
#!/usr/local/bin/dash
# lead_zeros.sh

# This is a gotcha...
# There will always be 6 zeros sooner or later, 000000.
 
# Only the last 6 digits are really needed... 
TEST_VAL=0.000000
TEST_NUM=123

num=${TEST_VAL#??}
echo "${num}"
lz=${num%%[1-9]*}
echo "${lz}"
TEST_VAL=${num#$lz}

echo "Test value = ${TEST_VAL}..."

TEST_VAL=$(( TEST_VAL * TEST_NUM ))

echo "Required integer = ${TEST_VAL}..."

Results:
Code:
Last login: Mon Jan 20 21:18:42 on ttys000
AMIGA:amiga~> cd Desktop/Code/Shell
AMIGA:amiga~/Desktop/Code/Shell> chmod 755 lead_zeros.sh
AMIGA:amiga~/Desktop/Code/Shell> ./lead_zeros.sh
000000
000000
Test value = ...
./lead_zeros.sh: 19: ./lead_zeros.sh: Illegal number: 
AMIGA:amiga~/Desktop/Code/Shell> _

EDIT:
This is a workaround...
TEST_VAL=$(( (${TEST_VAL} + 0 ) * TEST_NUM ))

Last edited by wisecracker; 01-20-2020 at 06:46 PM.. Reason: See EDIT:
 

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Tk_GetDash(3)						       Tk Library Procedures						     Tk_GetDash(3)

__________________________________________________________________________________________________________________________________________________

NAME
Tk_GetDash - convert from string to valid dash structure. SYNOPSIS
#include <tk.h> int Tk_GetDash(interp, string, dashPtr) ARGUMENTS
Tcl_Interp *interp (in) Interpreter to use for error reporting. const char * string (in) Textual value to be converted. Tk_Dash *dashPtr (out) Points to place to store the dash pattern value converted from string. _________________________________________________________________ DESCRIPTION
These procedure parses the string and fills in the result in the Tk_Dash structure. The string can be a list of integers or a character string containing only ".,-_" or spaces. If all goes well, TCL_OK is returned. If string does not have the proper syntax then TCL_ERROR is returned, an error message is left in the interpreter's result, and nothing is stored at *dashPtr. The first possible syntax is a list of integers. Each element represents the number of pixels of a line segment. Only the odd segments are drawn using the "outline" color. The other segments are drawn transparent. The second possible syntax is a character list containing only 5 possible characters ".,-_ ". The space can be used to enlarge the space between other line elements, and can not occur as the first position in the string. Some examples: -dash . = -dash {2 4} -dash - = -dash {6 4} -dash -. = -dash {6 4 2 4} -dash -.. = -dash {6 4 2 4 2 4} -dash {. } = -dash {2 8} -dash , = -dash {4 4} The main difference of this syntax with the previous is that it is shape-conserving. This means that all values in the dash list will be multiplied by the line width before display. This assures that "." will always be displayed as a dot and "-" always as a dash regardless of the line width. On systems where only a limited set of dash patterns, the dash pattern will be displayed as the most close dash pattern that is available. For example, on Windows only the first 4 of the above examples are available. The last 2 examples will be displayed identically as the first one. KEYWORDS
dash, conversion Tk 8.3 Tk_GetDash(3)
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