You can try attached hello1.rar using scanf().
hello1.rar (83.5 KB)
root@swi-mdm9x28-wp:~# app runProc hello1 hello1 --exe=hello1
Enter any character
1
Entered character is 1
Enter any string ( upto 100 character )
qwert
Entered string is qwert
^C
root@swi-mdm9x28-wp:~# legato version
19.02.0_4cb954265427b8c2c668a010ff5be274_modified
root@swi-mdm9x28-wp:~# cm info
Device: WP7609
IMEI: 359782080100399
IMEISV: 6
FSN: WA803370010610
Firmware Version: SWI9X07Y_02.28.03.05 000000 jenki[ 1778.268845] i2c-msm-v2 78b8000.i2c: NACK: slave not responding, ensure its powered: msgs(n:1 cur:0 tx) bc(rx:0 tx:2) mode:FIFO slv_addr:0x3a MSTR_STS:0x0c1300c8 OPER:0x00000090
ns 2019/07/08 11:04:16
Bootloader Version: SWI9X07Y_[ 1778.290372] i2c-msm-v2 78b8000.i2c: NACK: slave not responding, ensure its powered: msgs(n:1 cur:0 tx) bc(rx:0 tx:2) mode:FIFO slv_addr:0x3a MSTR_STS:0x0c1300c8 OPER:0x00000090
02.28.03.05 000000 jenkins 2019/07/08 11:04:16
MCU Version: 002.011
PRI Part Number (PN): 9908102
PRI Revision: 001.000
Carrier PRI Name: GENERIC
Carrier PRI Revision: 002.073_000
SKU: 1103843
Last Reset Cause: Power Down
Resets Count: Expected: 195 Unexpected: 243